def test_basic4():
    assert limit(2*x + y*x, x, 0) == 0
    assert limit(2*x + y*x, x, 1) == 2 + y
    assert limit(2*x**8 + y*x**(-3), x, -2) == 512 - y/8
    assert limit(sqrt(x) - sqrt(x + 1), x, oo) == 0
    assert integrate(1/(x**3 + 1), (x, 0, oo)) == 2*pi*sqrt(3)/9
dataset/ETHPy150Open sympy/sympy/sympy/series/tests/test_limits.py/test_basic4/swapped operands of `-`