def test_integrate_linearterm_pow():
    # check integrate((a*x+b)^c, x)  --  issue 3499
    y = Symbol('y', positive=True)
    # TODO: Remove conds='none' below, let the assumption take care of it.
    assert integrate(x**y, x, conds='none') == x**(y + 1)/(y + 1)
    assert integrate((exp(y)*x + 1/y)**(1 + sin(y)), x, conds='none') == \
        exp(-y)*(exp(y)*x + 1/y)**(2 + sin(y)) / (2 + sin(y))

def test_cross_method():
    N = NewtonianReferenceFrame('N')
    q, qd = N.declare_coords('q', 3)
    q1, q2, q3 = q
    A = N.rotate('A', 1, q1)
    B = N.rotate('B', 2, q2)
    C = N.rotate('C', 3, q3)
    assert cross(N[1], N[1]) == Vector(0) == 0
    assert cross(N[1], N[2]) == N[3]
    assert N[1].cross(N[3]) == Vector({N[2]: -1})

    assert N[2].cross(N[1]) == Vector({N[3]: -1})
    assert N[2].cross(N[2]) == Vector(0)
    assert N[2].cross(N[3]) == N[1]

    assert N[3].cross(N[1]) == N[2]
    assert N[3].cross(N[2]) == Vector({N[1]: -1})
    assert N[3].cross(N[3]) == Vector(0)

    assert N[1].cross(A[1]) == Vector(0)
    assert N[1].cross(A[2]) == A[3]
    assert N[1].cross(A[3]) == Vector(-A[2])

    assert N[2].cross(A[1]) == Vector(-N[3])
    assert N[2].cross(A[2]) == Vector(sin(q1)*N[1])
    assert N[2].cross(A[3]) == Vector(cos(q1)*N[1])

    assert N[1].cross(B[1]) == Vector(sin(q2)*N[2])
    assert N[1].cross(B[2]) == N[3]
    assert N[1].cross(B[3]) == Vector(-cos(q2)*N[2])

def test_cot_rewrite():
    x = Symbol('x')
    neg_exp, pos_exp = exp(-x*I), exp(x*I)
    assert cot(x).rewrite(exp) == I*(pos_exp+neg_exp)/(pos_exp-neg_exp)
    assert cot(x).rewrite(sin) == 2*sin(2*x)/sin(x)**2
    assert cot(x).rewrite(cos) == -cos(x)/cos(x + S.Pi/2)
    assert cot(x).rewrite(tan) == 1/tan(x)

def test_has_basics():
    f = Function("f")
    g = Function("g")
    p = Wild("p")

    assert sin(x).has(x)
    assert sin(x).has(sin)
    assert not sin(x).has(y)
    assert not sin(x).has(cos)
    assert f(x).has(x)
    assert f(x).has(f)
    assert not f(x).has(y)
    assert not f(x).has(g)

    assert f(x).diff(x).has(x)
    assert f(x).diff(x).has(f)
    assert f(x).diff(x).has(Derivative)
    assert not f(x).diff(x).has(y)
    assert not f(x).diff(x).has(g)
    assert not f(x).diff(x).has(sin)

    assert (x ** 2).has(Symbol)
    assert not (x ** 2).has(Wild)
    assert (2 * p).has(Wild)

    assert not x.has()

def test_image_interval():
    from sympy.core.numbers import Rational
    x = Symbol('x', real=True)
    a = Symbol('a', real=True)
    assert imageset(x, 2*x, Interval(-2, 1)) == Interval(-4, 2)
    assert imageset(x, 2*x, Interval(-2, 1, True, False)) == \
        Interval(-4, 2, True, False)
    assert imageset(x, x**2, Interval(-2, 1, True, False)) == \
        Interval(0, 4, False, True)
    assert imageset(x, x**2, Interval(-2, 1)) == Interval(0, 4)
    assert imageset(x, x**2, Interval(-2, 1, True, False)) == \
        Interval(0, 4, False, True)
    assert imageset(x, x**2, Interval(-2, 1, True, True)) == \
        Interval(0, 4, False, True)
    assert imageset(x, (x - 2)**2, Interval(1, 3)) == Interval(0, 1)
    assert imageset(x, 3*x**4 - 26*x**3 + 78*x**2 - 90*x, Interval(0, 4)) == \
        Interval(-35, 0)  # Multiple Maxima
    assert imageset(x, x + 1/x, Interval(-oo, oo)) == Interval(-oo, -2) \
        + Interval(2, oo)  # Single Infinite discontinuity
    assert imageset(x, 1/x + 1/(x-1)**2, Interval(0, 2, True, False)) == \
        Interval(Rational(3, 2), oo, False)  # Multiple Infinite discontinuities

    # Test for Python lambda
    assert imageset(lambda x: 2*x, Interval(-2, 1)) == Interval(-4, 2)

    assert imageset(Lambda(x, a*x), Interval(0, 1)) == \
            ImageSet(Lambda(x, a*x), Interval(0, 1))

    assert imageset(Lambda(x, sin(cos(x))), Interval(0, 1)) == \
            ImageSet(Lambda(x, sin(cos(x))), Interval(0, 1))

def test_dmp_clear_denoms():
    assert dmp_clear_denoms([[]], 1, QQ, ZZ) == (ZZ(1), [[]])

    assert dmp_clear_denoms([[QQ(1)]], 1, QQ, ZZ) == (ZZ(1), [[QQ(1)]])
    assert dmp_clear_denoms([[QQ(7)]], 1, QQ, ZZ) == (ZZ(1), [[QQ(7)]])

    assert dmp_clear_denoms([[QQ(7, 3)]], 1, QQ) == (ZZ(3), [[QQ(7)]])
    assert dmp_clear_denoms([[QQ(7, 3)]], 1, QQ, ZZ) == (ZZ(3), [[QQ(7)]])

    assert dmp_clear_denoms(
        [[QQ(3)], [QQ(1)], []], 1, QQ, ZZ) == (ZZ(1), [[QQ(3)], [QQ(1)], []])
    assert dmp_clear_denoms([[QQ(
        1)], [QQ(1, 2)], []], 1, QQ, ZZ) == (ZZ(2), [[QQ(2)], [QQ(1)], []])

    assert dmp_clear_denoms([QQ(3), QQ(
        1), QQ(0)], 0, QQ, ZZ, convert=True) == (ZZ(1), [ZZ(3), ZZ(1), ZZ(0)])
    assert dmp_clear_denoms([QQ(1), QQ(1, 2), QQ(
        0)], 0, QQ, ZZ, convert=True) == (ZZ(2), [ZZ(2), ZZ(1), ZZ(0)])

    assert dmp_clear_denoms([[QQ(3)], [QQ(
        1)], []], 1, QQ, ZZ, convert=True) == (ZZ(1), [[QQ(3)], [QQ(1)], []])
    assert dmp_clear_denoms([[QQ(1)], [QQ(1, 2)], []], 1, QQ, ZZ,
                            convert=True) == (ZZ(2), [[QQ(2)], [QQ(1)], []])

    assert dmp_clear_denoms(
        [[EX(S(3)/2)], [EX(S(9)/4)]], 1, EX) == (EX(4), [[EX(6)], [EX(9)]])
    assert dmp_clear_denoms([[EX(7)]], 1, EX) == (EX(1), [[EX(7)]])
    assert dmp_clear_denoms([[EX(sin(x)/x), EX(0)]], 1, EX) == (EX(x), [[EX(sin(x)), EX(0)]])

def test_as_ordered_terms():
    f, g = symbols("f,g", cls=Function)

    assert x.as_ordered_terms() == [x]
    assert (sin(x) ** 2 * cos(x) + sin(x) * cos(x) ** 2 + 1).as_ordered_terms() == [
        sin(x) ** 2 * cos(x),
        sin(x) * cos(x) ** 2,
        1,
    ]

    args = [f(1), f(2), f(3), f(1, 2, 3), g(1), g(2), g(3), g(1, 2, 3)]
    expr = Add(*args)

    assert expr.as_ordered_terms() == args

    assert (1 + 4 * sqrt(3) * pi * x).as_ordered_terms() == [4 * pi * x * sqrt(3), 1]

    assert (2 + 3 * I).as_ordered_terms() == [2, 3 * I]
    assert (-2 + 3 * I).as_ordered_terms() == [-2, 3 * I]
    assert (2 - 3 * I).as_ordered_terms() == [2, -3 * I]
    assert (-2 - 3 * I).as_ordered_terms() == [-2, -3 * I]

    assert (4 + 3 * I).as_ordered_terms() == [4, 3 * I]
    assert (-4 + 3 * I).as_ordered_terms() == [-4, 3 * I]
    assert (4 - 3 * I).as_ordered_terms() == [4, -3 * I]
    assert (-4 - 3 * I).as_ordered_terms() == [-4, -3 * I]

    f = x ** 2 * y ** 2 + x * y ** 4 + y + 2

    assert f.as_ordered_terms(order="lex") == [x ** 2 * y ** 2, x * y ** 4, y, 2]
    assert f.as_ordered_terms(order="grlex") == [x * y ** 4, x ** 2 * y ** 2, y, 2]
    assert f.as_ordered_terms(order="rev-lex") == [2, y, x * y ** 4, x ** 2 * y ** 2]
    assert f.as_ordered_terms(order="rev-grlex") == [2, y, x ** 2 * y ** 2, x * y ** 4]

def test_ode_solutions():
    # only a few examples here, the rest will be tested in the actual dsolve tests
    assert constant_renumber(constantsimp(C1*exp(2*x)+exp(x)*(C2+C3), x, 3), 'C', 1, 3) == \
        constant_renumber(C1*exp(x)+C2*exp(2*x), 'C', 1, 2)
    assert constant_renumber(constantsimp(Eq(f(x),I*C1*sinh(x/3) + C2*cosh(x/3)), x, 2),
        'C', 1, 2) == constant_renumber(Eq(f(x), C1*sinh(x/3) + C2*cosh(x/3)), 'C', 1, 2)
    assert constant_renumber(constantsimp(Eq(f(x),acos((-C1)/cos(x))), x, 1), 'C', 1, 1) == \
        Eq(f(x),acos(C1/cos(x)))
    assert constant_renumber(constantsimp(Eq(log(f(x)/C1) + 2*exp(x/f(x)), 0), x, 1),
        'C', 1, 1) ==  Eq(log(C1*f(x)) + 2*exp(x/f(x)), 0)
    assert constant_renumber(constantsimp(Eq(log(x*sqrt(2)*sqrt(1/x)*sqrt(f(x))\
        /C1) + x**2/(2*f(x)**2), 0), x, 1), 'C', 1, 1) == \
        Eq(log(C1*x*sqrt(1/x)*sqrt(f(x))) + x**2/(2*f(x)**2), 0)
    assert constant_renumber(constantsimp(Eq(-exp(-f(x)/x)*sin(f(x)/x)/2 + log(x/C1) - \
        cos(f(x)/x)*exp(-f(x)/x)/2, 0), x, 1), 'C', 1, 1) == \
        Eq(-exp(-f(x)/x)*sin(f(x)/x)/2 + log(C1*x) - cos(f(x)/x)*exp(-f(x)/x)/2, 0)
    u2 = Symbol('u2')
    _a = Symbol('_a')
    assert constant_renumber(constantsimp(Eq(-Integral(-1/(sqrt(1 - u2**2)*u2), \
        (u2, _a, x/f(x))) + log(f(x)/C1), 0), x, 1), 'C', 1, 1) == \
        Eq(-Integral(-1/(u2*sqrt(1 - u2**2)), (u2, _a, x/f(x))) + \
        log(C1*f(x)), 0)
    assert [constant_renumber(constantsimp(i, x, 1), 'C', 1, 1) for i in
        [Eq(f(x), sqrt(-C1*x + x**2)), Eq(f(x), -sqrt(-C1*x +
        x**2))]] == [Eq(f(x), sqrt(C1*x + x**2)),
        Eq(f(x), -sqrt(C1*x + x**2))]

def test_pend():
    q, u = dynamicsymbols('q u')
    qd, ud = dynamicsymbols('q u', 1)
    m, l, g = symbols('m l g')
    N = ReferenceFrame('N')
    P = Point('P')
    P.set_vel(N, -l * u * sin(q) * N.x + l * u * cos(q) * N.y)
    kd = [qd - u]

    FL = [(P, m * g * N.x)]
    pa = Particle()
    pa.mass = m
    pa.point = P
    BL = [pa]

    KM = Kane(N)
    KM.coords([q])
    KM.speeds([u])
    KM.kindiffeq(kd)
    KM.kanes_equations(FL, BL)
    MM = KM.mass_matrix
    forcing = KM.forcing
    rhs = MM.inv() * forcing
    rhs.simplify()
    assert expand(rhs[0]) == expand(-g / l * sin(q))

def func2b(x, y, out, alpha, beta):
    from numpy import sin, cos
    out *= beta
    out += alpha*np.array(
            [[    x*cos(y),    x*cos(y)**2, x*cos(y)**2*sin(y) ],
             [ x**2*cos(y), x**2*sin(y)**2,     x**2*sin(y)**3 ],
             [ x**3*cos(y), x**3*cos(y)**2,     x**3*sin(y)**3 ]])

def test_solve_sqrt_3():
    R = Symbol("R")
    eq = sqrt(2) * R * sqrt(1 / (R + 1)) + (R + 1) * (sqrt(2) * sqrt(1 / (R + 1)) - 1)
    sol = solveset_complex(eq, R)

    assert sol == FiniteSet(
        *[
            S(5) / 3 + 4 * sqrt(10) * cos(atan(3 * sqrt(111) / 251) / 3) / 3,
            -sqrt(10) * cos(atan(3 * sqrt(111) / 251) / 3) / 3
            + 40 * re(1 / ((-S(1) / 2 - sqrt(3) * I / 2) * (S(251) / 27 + sqrt(111) * I / 9) ** (S(1) / 3))) / 9
            + sqrt(30) * sin(atan(3 * sqrt(111) / 251) / 3) / 3
            + S(5) / 3
            + I
            * (
                -sqrt(30) * cos(atan(3 * sqrt(111) / 251) / 3) / 3
                - sqrt(10) * sin(atan(3 * sqrt(111) / 251) / 3) / 3
                + 40 * im(1 / ((-S(1) / 2 - sqrt(3) * I / 2) * (S(251) / 27 + sqrt(111) * I / 9) ** (S(1) / 3))) / 9
            ),
        ]
    )

    # the number of real roots will depend on the value of m: for m=1 there are 4
    # and for m=-1 there are none.
    eq = -sqrt((m - q) ** 2 + (-m / (2 * q) + S(1) / 2) ** 2) + sqrt(
        (-m ** 2 / 2 - sqrt(4 * m ** 4 - 4 * m ** 2 + 8 * m + 1) / 4 - S(1) / 4) ** 2
        + (m ** 2 / 2 - m - sqrt(4 * m ** 4 - 4 * m ** 2 + 8 * m + 1) / 4 - S(1) / 4) ** 2
    )
    raises(NotImplementedError, lambda: solveset_real(eq, q))

def test_ode_solutions():
    # only a few examples here, the rest will be tested in the actual dsolve tests
    assert ode_renumber(constantsimp(C1*exp(2*x)+exp(x)*(C2+C3), x, 3), 'C', 1, 3) == \
        ode_renumber(C1*exp(x)+C2*exp(2*x), 'C', 1, 2)
    assert ode_renumber(constantsimp(Eq(f(x),I*C1*sinh(x/3) + C2*cosh(x/3)), x, 2),
        'C', 1, 2) == ode_renumber(Eq(f(x), C1*sinh(x/3) + C2*cosh(x/3)), 'C', 1, 2)
    assert ode_renumber(constantsimp(Eq(f(x),acos((-C1)/cos(x))), x, 1), 'C', 1, 1) == \
        Eq(f(x),acos(C1/cos(x)))
    assert ode_renumber(constantsimp(Eq(log(f(x)/C1) + 2*exp(x/f(x)), 0), x, 1),
        'C', 1, 1) ==  Eq(log(C1*f(x)) + 2*exp(x/f(x)), 0)
    assert ode_renumber(constantsimp(Eq(log(x*2**Rational(1,2)*(1/x)**Rational(1,2)*f(x)\
        **Rational(1,2)/C1) + x**2/(2*f(x)**2), 0), x, 1), 'C', 1, 1) == \
        Eq(log(C1*x*(1/x)**Rational(1,2)*f(x)**Rational(1,2)) + x**2/(2*f(x)**2), 0)
    assert ode_renumber(constantsimp(Eq(-exp(-f(x)/x)*sin(f(x)/x)/2 + log(x/C1) - \
        cos(f(x)/x)*exp(-f(x)/x)/2, 0), x, 1), 'C', 1, 1) == \
        Eq(-exp(-f(x)/x)*sin(f(x)/x)/2 + log(C1*x) - cos(f(x)/x)*exp(-f(x)/x)/2, 0)
    u2 = Symbol('u2')
    _a = Symbol('_a')
    assert ode_renumber(constantsimp(Eq(-Integral(-1/((1 - u2**2)**Rational(1,2)*u2), \
        (u2, _a, x/f(x))) + log(f(x)/C1), 0), x, 1), 'C', 1, 1) == \
        Eq(-Integral(-1/(u2*(1 - u2**2)**Rational(1,2)), (u2, _a, x/f(x))) + \
        log(C1*f(x)), 0)
    assert map(lambda i: ode_renumber(constantsimp(i, x, 1), 'C', 1, 1),
        [Eq(f(x), (-C1*x + x**2)**Rational(1,2)), Eq(f(x), -(-C1*x +
        x**2)**Rational(1,2))]) == [Eq(f(x), (C1*x + x**2)**Rational(1,2)),
        Eq(f(x), -(C1*x + x**2)**Rational(1,2))]

def test_expand_integral():
    assert Integral(cos(x**2)*(sin(x**2) + 1), (x, 0, 1)).expand() == \
        Integral(cos(x**2)*sin(x**2), (x, 0, 1)) + \
        Integral(cos(x**2), (x, 0, 1))
    assert Integral(cos(x**2)*(sin(x**2) + 1), x).expand() == \
        Integral(cos(x**2)*sin(x**2), x) + \
        Integral(cos(x**2), x)

def test_transform():
    a = Integral(x**2 + 1, (x, -1, 2))
    fx = x
    fy = 3*y + 1
    assert a.doit() == a.transform(fx, fy).doit()
    assert a.transform(fx, fy).transform(fy, fx) == a
    fx = 3*x + 1
    fy = y
    assert a.transform(fx, fy).transform(fy, fx) == a
    a = Integral(sin(1/x), (x, 0, 1))
    assert a.transform(x, 1/y) == Integral(sin(y)/y**2, (y, 1, oo))
    assert a.transform(x, 1/y).transform(y, 1/x) == a
    a = Integral(exp(-x**2), (x, -oo, oo))
    assert a.transform(x, 2*y) == Integral(2*exp(-4*y**2), (y, -oo, oo))
    # < 3 arg limit handled properly
    assert Integral(x, x).transform(x, a*y).doit() == \
        Integral(y*a**2, y).doit()
    _3 = S(3)
    assert Integral(x, (x, 0, -_3)).transform(x, 1/y).doit() == \
        Integral(-1/x**3, (x, -oo, -1/_3)).doit()
    assert Integral(x, (x, 0, _3)).transform(x, 1/y) == \
        Integral(y**(-3), (y, 1/_3, oo))
    # issue 8400
    i = Integral(x + y, (x, 1, 2), (y, 1, 2))
    assert i.transform(x, (x + 2*y, x)).doit() == \
        i.transform(x, (x + 2*z, x)).doit() == 3

def trig_rule(integral):
    integrand, symbol = integral
    if isinstance(integrand, sympy.sin) or isinstance(integrand, sympy.cos):
        arg = integrand.args[0]

        if not isinstance(arg, sympy.Symbol):
            return  # perhaps a substitution can deal with it

        if isinstance(integrand, sympy.sin):
            func = "sin"
        else:
            func = "cos"

        return TrigRule(func, arg, integrand, symbol)

    if integrand == sympy.sec(symbol) ** 2:
        return TrigRule("sec**2", symbol, integrand, symbol)
    elif integrand == sympy.csc(symbol) ** 2:
        return TrigRule("csc**2", symbol, integrand, symbol)

    if isinstance(integrand, sympy.tan):
        rewritten = sympy.sin(*integrand.args) / sympy.cos(*integrand.args)
    elif isinstance(integrand, sympy.cot):
        rewritten = sympy.cos(*integrand.args) / sympy.sin(*integrand.args)
    elif isinstance(integrand, sympy.sec):
        arg = integrand.args[0]
        rewritten = (sympy.sec(arg) ** 2 + sympy.tan(arg) * sympy.sec(arg)) / (sympy.sec(arg) + sympy.tan(arg))
    elif isinstance(integrand, sympy.csc):
        arg = integrand.args[0]
        rewritten = (sympy.csc(arg) ** 2 + sympy.cot(arg) * sympy.csc(arg)) / (sympy.csc(arg) + sympy.cot(arg))
    else:
        return

    return RewriteRule(rewritten, integral_steps(rewritten, symbol), integrand, symbol)

def test_evalf_bugs():
    assert NS(sin(1)+exp(-10**10),10) == NS(sin(1),10)
    assert NS(exp(10**10)+sin(1),10) == NS(exp(10**10),10)
    assert NS('log(1+1/10**50)',20) == '1.0000000000000000000e-50'
    assert NS('log(10**100,10)',10) == '100.0000000'
    assert NS('log(2)',10) == '0.6931471806'
    assert NS('(sin(x)-x)/x**3', 15, subs={x:'1/10**50'}) == '-0.166666666666667'
    assert NS(sin(1)+Rational(1,10**100)*I,15) == '0.841470984807897 + 1.00000000000000e-100*I'
    assert x.evalf() == x
    assert NS((1+I)**2*I, 6) == '-2.00000'
    d={n: (-1)**Rational(6,7), y: (-1)**Rational(4,7), x: (-1)**Rational(2,7)}
    assert NS((x*(1+y*(1 + n))).subs(d).evalf(),6) == '0.346011 + 0.433884*I'
    assert NS(((-I-sqrt(2)*I)**2).evalf()) == '-5.82842712474619'
    assert NS((1+I)**2*I,15) == '-2.00000000000000'
    #1659 (1/2):
    assert NS(pi.evalf(69) - pi) == '-4.43863937855894e-71'
    #1659 (2/2): With the bug present, this still only fails if the
    # terms are in the order given here. This is not generally the case,
    # because the order depends on the hashes of the terms.
    assert NS(20 - 5008329267844*n**25 - 477638700*n**37 - 19*n,
              subs={n:.01}) == '19.8100000000000'
    assert NS(((x - 1)*((1 - x))**1000).n()) == '(-x + 1.00000000000000)**1000*(x - 1.00000000000000)'
    assert NS((-x).n()) == '-x'
    assert NS((-2*x).n()) == '-2.00000000000000*x'
    assert NS((-2*x*y).n()) == '-2.00000000000000*x*y'

def test_manualintegrate_derivative():
    assert manualintegrate(pi * Derivative(x**2 + 2*x + 3), x) == \
        pi * ((x**2 + 2*x + 3))
    assert manualintegrate(Derivative(x**2 + 2*x + 3, y), x) == \
        Integral(Derivative(x**2 + 2*x + 3, y))
    assert manualintegrate(Derivative(sin(x), x, x, x, y), x) == \
        Derivative(sin(x), x, x, y)

def test_as_real_imag():
    n = pi**1000
    # the special code for working out the real
    # and complex parts of a power with Integer exponent
    # should not run if there is no imaginary part, hence
    # this should not hang
    assert n.as_real_imag() == (n, 0)

    # issue 6261
    x = Symbol('x')
    assert sqrt(x).as_real_imag() == \
        ((re(x)**2 + im(x)**2)**(S(1)/4)*cos(atan2(im(x), re(x))/2),
     (re(x)**2 + im(x)**2)**(S(1)/4)*sin(atan2(im(x), re(x))/2))

    # issue 3853
    a, b = symbols('a,b', real=True)
    assert ((1 + sqrt(a + b*I))/2).as_real_imag() == \
           (
               (a**2 + b**2)**Rational(
                   1, 4)*cos(atan2(b, a)/2)/2 + Rational(1, 2),
               (a**2 + b**2)**Rational(1, 4)*sin(atan2(b, a)/2)/2)

    assert sqrt(a**2).as_real_imag() == (sqrt(a**2), 0)
    i = symbols('i', imaginary=True)
    assert sqrt(i**2).as_real_imag() == (0, abs(i))

def test_special_is_rational():
    i = Symbol('i', integer=True)
    r = Symbol('r', rational=True)
    x = Symbol('x')
    assert sqrt(3).is_rational is False
    assert (3 + sqrt(3)).is_rational is False
    assert (3*sqrt(3)).is_rational is False
    assert exp(3).is_rational is False
    assert exp(i).is_rational is False
    assert exp(r).is_rational is False
    assert exp(x).is_rational is None
    assert exp(log(3), evaluate=False).is_rational is True
    assert log(exp(3), evaluate=False).is_rational is True
    assert log(3).is_rational is False
    assert log(i).is_rational is False
    assert log(r).is_rational is False
    assert log(x).is_rational is None
    assert (sqrt(3) + sqrt(5)).is_rational is None
    assert (sqrt(3) + S.Pi).is_rational is None
    assert (x**i).is_rational is None
    assert (i**i).is_rational is True
    assert (r**i).is_rational is True
    assert (r**r).is_rational is None
    assert (r**x).is_rational is None
    assert sin(1).is_rational is False
    assert sin(i).is_rational is False
    assert sin(r).is_rational is False
    assert sin(x).is_rational is None
    assert asin(r).is_rational is False
    assert sin(asin(3), evaluate=False).is_rational is True

def test_equals():
    assert (-3 - sqrt(5) + (-sqrt(10) / 2 - sqrt(2) / 2) ** 2).equals(0)
    assert (x ** 2 - 1).equals((x + 1) * (x - 1))
    assert (cos(x) ** 2 + sin(x) ** 2).equals(1)
    assert (a * cos(x) ** 2 + a * sin(x) ** 2).equals(a)
    r = sqrt(2)
    assert (-1 / (r + r * x) + 1 / r / (1 + x)).equals(0)
    assert factorial(x + 1).equals((x + 1) * factorial(x))
    assert sqrt(3).equals(2 * sqrt(3)) is False
    assert (sqrt(5) * sqrt(3)).equals(sqrt(3)) is False
    assert (sqrt(5) + sqrt(3)).equals(0) is False
    assert (sqrt(5) + pi).equals(0) is False
    assert meter.equals(0) is False
    assert (3 * meter ** 2).equals(0) is False

    # from integrate(x*sqrt(1+2*x), x);
    # diff is zero, but differentiation does not show it
    i = 2 * sqrt(2) * x ** (S(5) / 2) * (1 + 1 / (2 * x)) ** (S(5) / 2) / 5 + 2 * sqrt(2) * x ** (S(3) / 2) * (
        1 + 1 / (2 * x)
    ) ** (S(5) / 2) / (-6 - 3 / x)
    ans = sqrt(2 * x + 1) * (6 * x ** 2 + x - 1) / 15
    diff = i - ans
    assert diff.equals(0) is not False  # should be True, but now it's None
    # XXX TODO add a force=True option to equals to posify both
    # self and other before beginning comparisions
    p = Symbol("p", positive=True)
    assert diff.subs(x, p).equals(0) is True