1.已知实数x,y满足x=(根号y-3 )+(根号3-y)+2,求x的y次方的值.(
问题描述:
1.已知实数x,y满足x=(根号y-3 )+(根号3-y)+2,求x的y次方的值.(
答
y=3,x=2,答案是8
答
x=根号(y-3 )+根号(3-y)+2
实数范围内根号下无负数:(y-3 )≥0,(3-y)≥0
∴y-3=3-y=0
∴y=3
∴x=根号(y-3 )+根号(3-y)+2=0+0+2=2
x的y次方=2^3=8