A = (2x + 3)2 - (2x - 3)(2x + 3)
= 4x2 + 12x + 9 - 4x2 + 9
= 12x +18
Rút gọn biểu thức sau A=(2x+3)^2-(2x-3)×(2x+3)
trả lời:
\(A=\left(2x+3^2\right)-\left(2x-3\right).\left(2x+3\right)\)
\(=4x^2+12x+9-4x^2+9\)
\(=12x+8\)
\(=20\)
Vậy \(x=20\)
học tốt
\(A=\left(2x+3\right)^2-\left(2x-3\right)\left(2x+3\right)\)
\(A=\left(2x+3\right)\left(2x+3-2x+3\right)\)
\(A=\left(2x+3\right)6\)
\(A=12x+18\)