问题
填空题
已知ab=6,a+b=5,则a3b+2a2b2+ab3的值为______.
答案
∵a3b+2a2b2+ab3,
=ab(a2+b2+2ab),
=ab(a+b)2;
∵a+b=5,
∴(a+b)2=25,
∵ab=6,
∴原式=6×25=150.
故答案为:150.
已知ab=6,a+b=5,则a3b+2a2b2+ab3的值为______.
∵a3b+2a2b2+ab3,
=ab(a2+b2+2ab),
=ab(a+b)2;
∵a+b=5,
∴(a+b)2=25,
∵ab=6,
∴原式=6×25=150.
故答案为:150.