Giúp mình câu này với!làm ơn!
\(C=\left(x-2\right)\left(x+2\right)-\left(x-3\right)\left(x+1\right)\)
\(=x^2-4-x^2-x+3x+3\)
\(=2x-1\)
Vậy...
\(C=\left(x-2\right).\left(x+2\right)-\left(x-3\right).\left(x+1\right)\)
\(C=x^2+2x-2x-4-x^2-x+3x+3\)
\(C=\left(x^2-x^2\right)+\left(2x-2x-x+3x\right)+\left(-4+3\right)\)
\(C=2x-1\)
Chúc bạn học tốt!!!
\(C=\left(x-2\right)\left(x+2\right)-\left(x-3\right)\left(x+1\right)\)
\(\Leftrightarrow C=x^2+2x-2x-4-x^2-x+3x+3\)
\(\Leftrightarrow C=2x-1\)
nà
\(C=\left(x-2\right)\left(x+2\right)-\left(x-3\right)\left(x+1\right)\)
\(=x^2-4-x^2-x+3x+1=2x-3\)
C=(x-2)(x+2)-(x-3)(x+1)
=x2-4-x2-x+3x+1=2x-3
giúp em câu 6,9,10 câu này khó em k làm dc
