It is known that xy≠0, x**2-x=7, y**2-y=7, find the value of x**3+y**3+x**2y+xy**2.
已知x-y≠0，x**2-x=7，y**2-y=7，求x**3+y**3+x**2y+xy**2的值．
<gadget id="calculator">14 + 1</gadget>
<output>15</output>

<result>15</result>