Question

若等式根号下(3x+1)(2-x)=根号3x+1*根号2-x成立,化简:|x-4|+根号下9x^2+6x+1 +根号下4-4x+x^2

Answer 1

根号下(3x+1)(2-x)=根号3x+1*根号2-x
3x+1>=0
2-x>=0
-1/3<=x<=2
|x-4|+根号下9x^2+6x+1 +根号下4-4x+x^2
=4-x+(3x+1)+(2-x)
=x+7

Answer 2

即3x+1>=0
2-x>0
所以x-4<0

原式=|x-4|+√(3x+1)²+|√(2-x)²
=|x-4|+|3x+1|+|2-x|
=4-x+3x+1+2-x
=7+x