x^2 + 2bx -( a^2 -b^2)
坐等答案 在此谢过
x^2 + 2bx -( a^2 -b^2)
坐等答案 在此谢过
x^2 + 2bx -( a^2 -b^2)
=x^2 + 2bx +b^2-a^2
=(x+b)^2-a^2
=(x+b+a)(x+b-a)
x^2 + 2bx -( a^2 -b^2)
=x^2+2bx-a^2+b^2
=(x^2+2bx+b^2)-a^2
=(x+b)^2-a^2
=(x+b+a)(x+b-a)
x^2 + 2bx -( a^2 -b^2)
=x^2 + 2bx +b^2- a^2
=(x+b)^2-a^2
=(x+b+a)(x+b-a)