方法一:
(x+6)² - (x - 6)²
= [(x+6)+(x - 6)]·[(x+6) - (x - 6)]
= 2x·12
=24x
方法二:
(x+6)² - (x - 6)²
= (x²+12x+36) - (x² - 12x+36)
= 24x
(x+6)²-(x-6)²=x²+2*6*x+6²-【x²-2*6*x+6²】=x²+2*6*x+6²-x²+2*6*x-6²=24x 望采纳 ,不懂可追问
(x+6)²—(x_6)² =【(x+6)-(x-6)】【(x+6)+(x-6)】=x^2+36+12x-x^2-36+12x=24x