Question

áp dụng hằng đẳng thức

 help mk vsssss mk đang càn gấp plssssss

Answer 1

\(a,\rightarrow6\left(x^2-3x+2x-6\right)-3\left(x^2-4x+4\right)-3\left(x^2-1\right)=1\)

\(\rightarrow6x^2-18x+12x-36-3x^2+12x-12-3x^2+3=1\\ \rightarrow6x^2-3x^2-3x^2-18x+12x+12x=1+36+12-3\\ \rightarrow6x=46\\\rightarrow x=\dfrac{23}{3}\)

\(b,\rightarrow3\left(x^2+4x+4\right)+\left(4x^2-4x+1\right)-7\left(x^2-9\right)=36\\ \rightarrow3x^2+12x+12+4x^2-4x+1-7x^2+63=36\\ \rightarrow3x^2+4x^2-7x^2+12x-4x=36-12-1-63\\ \rightarrow8x=-40\\ \rightarrow x=-5\)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Answer 2

ai help mk câu c và d vs