Question

x的3次方y的m-1次方*x的n+m次方y的2n+2次方=x的9次方y的9次方,则4m-3n的值是?

Answer 1

x^3y^(m-1)x^(n+m)y^(2n+2)

=x^(3+n+m)y^(m-1+2n+2)

=x^(m+n+3)y^(m+2n+1)

=x^9y^9

m+n+3=9

m+2n+1=9

解得

m=4 n=2

4m-3n=16-6=10

选C.