二次根式计算题70—40道不要超纲,只要二次根式随便给咱40道二次根式的计算题...过了周一就不要了.....

5个回答

  • 1.3√(1/6)-4√(50)+30√(2/3)

    答案3√(1/6)-4√(50)+30√(2/3)

    = 3×√6/6-4×5√2+30×√6/3

    =√6/2-20√2+10√6

    2.(1-根号2)/2乘以(1+根号2)/2

    题是这样的二分之一减根号2乘以二分之一加根号2

    答案:(1-根号2)/2乘以(1+根号2)/2

    =(1-√2)*(1-√2)/4

    =(1-2)/4

    =-1/4

    3.√(1/2x)^2+10/9x^2

    √[(1/2x)^2+10/9x^2]

    =√(x^2/4+10x^2/9)

    =√(9x^2/36+40x^2/36)

    =√(49x^2/36)

    =7|x|/6;

    4.√a^4mb^2n+1(a、b为正数)

    [√(a^4mb^2n)]+1(a、b为正数)

    =a^2mb^n+1;

    5.√(4a^5+8a^4)(a^2+3a+2)(a>=0)

    √[(4a^5+8a^4)(a^2+3a+2)](a>=0)

    =√[4a^4(a+2)(a+2)(a+1)]

    =√[(2a^2)^2(a+2)^2(a+1)]

    =2a^2(a+2)√(a+1).

    太多了呀,只能这样了,我还有事