Question

当x=4,y=16,时,求根号(x^3+x²y+1/4xy²)+根号(1/4x²y+xy²+y^3)的值。

急！今天就要的！谢谢！！

Answer 1

√(x^3+x²y+1/4xy²)+√(1/4x²y+xy²+y^3)

=√x*√(x^2+xy+1/4y²)+√y*√(1/4x²+xy+y^2)
=√x*√(x+y/2)^2+√y*√(1/2x+y)^2
=2*12+4*18
=96

Answer 2

解：当x=4,y=16时，x+1/2y=12，1/2x+y=18
∴原式=根号【x(x+1/2y)²】+根号【y(1/2x+y)²】
=12根号4+18根号16
=12*2+18*4
=96