9年级计算题要有过程解答
2011-10-29 20:17:41w***
要有过程解答。9年级计算题要有过程解答。:1.
=√(32*1/2)+2√5
=√16+2√5
=4+2√5
2.
=[3*2√3-(2/3)*√3+4√3]÷?
最佳回答
1.
=√(32*1/2)+2√5
=√16+2√5
=4+2√5
2.
=[3*2√3-(2/3)*√3+4√3]÷2√3
=[6-(2/3)+4]*√3÷2√3
=14/3
3.
x^2-2x-3=0
===> (x+1)*(x-3)=0
===> x1=-2,x2=3
4.
两者互为相反数,那么它们的和为零
即,(x^2-2x)+(2x^2-3x)=0
===> 3x^2-5x=0
===> x*(3x-5)=0
===> x1=0,或者x2=5/3.
2011-10-29 20:45:44
解:(1)原式=√(32*1/2)+√4*5
=√16+2√5
=4+2√5
(2)原式=3/2*√(12/3)-2/2*√[(1/3)/3]+√(48/3)/2
=3/2*2-1/3+2
=14/3
(3)(x-3)(x+1)=0
x=-1 或x=3
(4)x^2-2x=-(2x^2-3x)
3x^2-5x=0
x(3x-5)=0
x=0 或x=5/3
2011-10-29 21:02:44
很赞哦! (204)