Câu hỏi của Bảo Ngọc cute

Question

Rút gọn

(6x+1)2 + ( 6x-1)2 - 2(1+6x)(6x-1)

Mysterious Person · Accepted Answer

$\left(6x+1\right)^2+\left(6x-1\right)^2-2\left(1+6x\right)\left(6x-1\right)$

$=36x^2+12x+1+36x^2-12x+1-2\left(6x+1\right)\left(6x-1\right)$

$=72x^2+2-2\left(36x^2-1\right)=72x^2+2-72x^2+2=4$Câu trả lời: $\left(6x+1\right)^2+\left(6x-1\right)^2-2\left(1+6x\right)\left(6x-1\right)$

$=36x^2+12x+1+36x^2-12x+1-2\left(6x+1\right)\left(6x-1\right)$

$=72x^2+2-2\left(36x^2-1\right)=72x^2+2-72x^2+2=4$

Song Thư · Answer

$\left(6x+1\right)^2+\left(6x-1\right)^2-2\left(1+6x\right)\left(6x-1\right)$

$=\left(6x+1\right)^2-2\left(6x+1\right)\left(6x-1\right)+\left(6x-1\right)^2$

$=\left[\left(6x+1\right)-\left(6x-1\right)\right]^2$ (Hằng đẳng thức số 2)

$=2^2=4$Câu trả lời: $\left(6x+1\right)^2+\left(6x-1\right)^2-2\left(1+6x\right)\left(6x-1\right)$

$=\left(6x+1\right)^2-2\left(6x+1\right)\left(6x-1\right)+\left(6x-1\right)^2$

$=\left[\left(6x+1\right)-\left(6x-1\right)\right]^2$ (Hằng đẳng thức số 2)

$=2^2=4$

Violympic toán 8