Question

viết đẳng thức sau dưới dạng 1 lũy thừa

 a, 9x^2 - 6x + 1

 b, 4x^2 + 4x + 1

c, 4x^2 + 12xy + 9y^2

d, -4x^2 + 12xy - 9y^2

Answer 1

a)\(\left(3x\right)^2-2×3x+1^2=\left(3x-1\right)^2\)

b)\(\left(2x\right)^2+2×2x+1^2=\left(2x+1\right)^2\)

c)\(\left(2x\right)^2+2×2x×3y+\left(3y\right)^2=\left(2x+3y\right)^2\)

d)\(-\left(4x^2-12xy+9y^2\right)=-\left[\left(2x\right)^2-2×2x×3y+\left(3x\right)^2\right]=-\left[\left(2x-3y\right)^2\right]\)