Cours Stage - Factoriser une expression

Exercice - Factoriser une expression

L'énoncé

Factorisez les expressions suivantes :


Question 1

\(A = \dfrac{1}{5}x^2-\dfrac {1}{10}\)

\(A = \dfrac {1}{5}\left( x^2-\dfrac{1}{2}\right)\)

Question 2

\(B = -48x^2-160\)

\(B = -16(3x^2+10)\)

Question 3

\(C = 45x^2y-55xy^2+35xy\)

\(C = 5xy(9x -11y+7)\)

Question 4

\(D = (7x-4)(x+1)-3(x+1)\)

\(D = (x+1)(7x-4-3)\)
\(D = (x+1)(7x-7)\)
\(D = 7(x+1)(x-1)\)

Question 5

\(E = (-2x+7)(3x+5)-(2-22x)(7-2x)\)

\(E = (-2x+7)(3x+5)-(2-22x)(7-2x)\)
Le facteur commun est (\(7-2x)\)

\(E = (7-2x)[(3x+5)-(2-22x)]\)
\(E = (7-2x)[3x+5-2+22x]\)
\(E = (7-2x)(25x+3)\)