Question

Tìm x 49(x+1)^2-(3-x)^2=0

Answer 1

\(\Leftrightarrow\left(7x+7\right)^2-\left(x-3\right)^2=0\)

\(\Leftrightarrow\left(7x+7+x-3\right)\left(7x+7-x+3\right)=0\)

=>(8x+4)(6x+10)=0

=>x=-5/3 hoặc x=-1/2

Answer 2

49 (x + 1)² - (3 - x)² = 0

=> (7x + 7)² - (x - 3)² =  0

=> (7x + 7 + x - 3) (7x + 7 - x + 3) = 0

=> (8x + 4) (6x + 10) = 0

vậy x = [- 5/3 ;- 1/2]