def test_mrv_leadterm2():
    #Gruntz: p51, 3.25
    assert mrv_leadterm((log(exp(x) + x) - x)/log(exp(x) + log(x))*exp(x), x) == \
        (1, 0)

def test_mrv_leadterm3():
    #Gruntz: p56, 3.27
    assert mmrv(exp(-x + exp(-x)*exp(-x*log(x))), x) == set([exp(-x - x*log(x))])
    assert mrv_leadterm(exp(-x + exp(-x)*exp(-x*log(x))), x) == (exp(-x), 0)

def test_mrv_leadterm1():
    assert mrv_leadterm(-exp(1/x), x) == (-1, 0)
    assert mrv_leadterm(1/exp(-x + exp(-x)) - exp(x), x) == (-1, 0)
    assert mrv_leadterm(
        (exp(1/x - exp(-x)) - exp(1/x))*exp(x), x) == (-exp(1/x), 0)