bonjour
A(t) = (t+5) (-3t+1)
= - 3 t² + t - 15 t + 5
= - 3 t² - 14 t + 5
B(y) = (6y-1) (4/7-y)
= 24 y /7 - 6 y² - 4/7 + y
= - 6 y² + 24 y /7- 4 /7 + 7 y /7
= - 6 y² + 31 y /7 - 4 /7
C(z) = (1/3z+1) (1/3z-1)
= z² /9 - 1
2.Factoriser:
D= 4x*x+16x+40
= 4 ( x² + 4 x + 10 )
E= 35t*t+49t+7ty
= 7 t ( 5 t + 7 + y )
F= (3x-1)(4x+5)+(3x-1)(5x+1)
= ( 3 x - 1 ) ( 4 x + 5 + 5 x + 1 )
= ( 3 x - 1 ) ( 9 x + 6 )
= 3 ( 3 x - 1 ) ( 3 x + 2 )
