一个正方形的体积为8*10^12立方毫米,则它的棱长为多少毫米?(填空题,直接答案就行了!)
1个回答

第一题(8+12+10)*4=120

第二题-(a^2*b)*(2ab)^3+10*a^5*b^4

= -a^2 * b * 8 * a^3 * b^3 + 10 * a^5 * b^4

= -8 * a^5 * b^4 + 10 * a^5 * b^4

= 2 * a^5 * b^4

第三题(-2x^2)*(-y)+3xy*(1-1/3x)

= 2 * x^2 * y + 3xy - x^2 * y

= x^2 * y + 3xy

第四题当n为奇数时 x = [(-1) - (1)]/2 = -1

S = x+2x^2+3x^3+……+99x^99+100x^100

= -1 + 2 - 3 + ... - 99 + 100

= 1 + 1 + ... + 1 (50项)

= 50

当n为偶数时 x = [1 - (-1)]/2 = 1

S = x+2x^2+3x^3+……+99x^99+100x^100

= 1 + 2 + 3 + ... + 99 + 100

= 100 * (1 + 100) / 2

= 5050

第五题(2^3)^8 * 2^(-2)^12* (-1)^12

=2^(3*8)* 2^(-24)*1

=1