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X×(X+1)×(X+2)×(X+3)=360 这个怎么算?

[x(x+3)][(x+1)(x+2)]=360(这样做是为了让一次项系数相等) (x^2+3x)(x^2+3x+2)-360=0 (把x^2+3x看成一个整体) (x^2+3x)^2+2(x^2+3x)-360=0 (x^2+3x-18)(x^2+3x+20)=0 (x-3)(x+6)(x^2+3x+20)=0 x=3或x=-6

x(x+1)(x+2)(x+3)=360 x(x+1)(x+2)(x+3)=3x4x5x6=(-6)x(-5)x(-4)x(-3) x=3 或 x=-6

将式子变型为x(x+3)(x+1)(x+2)=360(x²+3x)(x²+3x+2)=360[(x²+3x+1)-1][(x²+3x+1)+1]=360(x²+3x+1)²-1²=360(x²+3x+1)²=361x²+3x+1=±19 将正负19分别代入得 x²+3x+20=0因为3²-4×20<...

x(x+1)(x+2)(x+3)=360 (x^2+3x)(x^2+3x+2)=360 (x^2+3x)^2+2(x^2+3x)-360=0 (x^2+3x+20)(x^2+3x-18)=0 因为 x^2+3x+20>0, 所以 x^2+3x-18=0 (x+6)(x-3)=0 所以 x1=-6, x2=3。

[n(n+3)][(n+1)(n+2)]-360=0 (n²+3n)(n²+3n+2)-360=0 (n²+3n)²+2(n²+3n)-360=0 (n²+3n-18)(n²+3n+20)=0 n²+3n+20=(n+ 3/2)²+71/4恒>0,因此只有n²+3n-18=0 (n+6)(n-3)=0 n=-6或n=3

(x+1)(x+2)(x+3)(x+4)-360 =[(x+1)(x+4)][(x+2)(x+3)]-360 =(x²+5x+4)(x²+5x+6)-360 =(x²+5x)²+10(x²+5x)+24-360 =(x²+5x)²+10(x²+5x)-336 =(x²+5x-14)(x²+5x+24) =(x-2)(x+7)(x²+5x+24)

(1)30X÷2=360, 30X÷2×2=360×2, 30X=720, 30X÷30=720÷30, X=24;(2)2.3X-1.02=0.36,2.3X-1.02+1.02=0.36+1.02, 2.3X=1.38, 2.3X÷2.3=1.38÷2.3, X=0.6;(3)8X-16=(X+1)×2, 8X-16=2X+2, 8X-16+16=2X+2+16, 8X=2X+18, 8X-2X=2X+...

a(a+1)(a+2)(a+3)=360 a(a+3)·(a+1)(a+2)=360 (a²+3a)(a²+3a+2)=360 (a²+3a)(a²+3a+2)-360=0 将a²+3a看成一个整体 令t=a²+3a 则t(t+2)-360=0 t²+2t-360=0 十字交叉法 (t-18)(t+20)=0 t=18或-2...

120

1/4÷x+3/7÷x+3/5÷x=360 两边同时乘以x 1/4+3/7+3/5=360x 179/140=360x x=179/50400

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