观察算式.1^3=1X1=1,1^3+2^3=3X3=9,1^3+2^3+3^3=6X6=36,1^3+2^3+3^3+
2个回答
1^3+2^3=(1+2)²=9,
1^3+2^3+3^3=(1+2+3)²=36,
1^+2^+3^+4^=(1+2+3+4)²=100
……
55^3
n²(n+1)²/4
相关问题
观察下列算式:1 3 =1=1 2 ;1 3 +2 3 =9=3 2 ;1 3 +2 3 +3 3 =36=6 2 ;1
观察以下等式:(x+1)(x2-x+1)=x3+1(x+3)(x2-3x+9)=x3+27(x+6)(x2-6x+36)
1-1/3(6x+9)=3(x+2/3)
解方程(1) 2 3x-1 -1= 3 6x-2 (2) 12 x 2 -9 + 2 3-x = 1 x+3 .
1/6(7X-3)-3X-1/2-1+3X/3=1
(X^3-1)/(X-1)= (9x^3-6X^2-5X+2)/(3X-1)=
(1) x/x+1-2/3x-3=1; (2) 1/9x-3-x/3x-1=2/3
1.2(3-y)-3(2/3y+1)=1 2.x/12-1=x/3 3.x/3-(x+2)/6=2 4.(2y-1)/3
(3x 1)^2=6(3x 1) 3
1/x(x+3)+1/(x+3)(x+6)+1/(x+6)(x+9)=3/2x+18