Réponse:
Bonsoir,
4t²-40t+100 = 4t²-40t+10²
→ (4t-10)²
(3u+8)²-81u²
→ (a+b)(a-b)= a²-b²
(3u+8-9u)(3u+8+9u)
=( -6u+8)( 12u+8)
24x+36x²+4= (6x)² +24x+2²
→ (6x+2)²
(5x-2)²-36x²
→ (5x-2+6x)(5x-2-6x)
= (11x-2)(-x-2)
16x²+36 +48x = (4x)²+ 48x + 6²
→ (4x+6)²
16x²+81-72x= (4x)²-72x +9²
→ (4x-9)²
identités remarquables :
(a+b)²= a²+2ab+b²
(a+b)(a-b)= a²-b²
(a-b)² = a²-2ab+b²
Bonne soirée.
