Bonsoir
A= ( 7 + √7 )² + ( 7 - √7 )²
A = 49 + 14 √7 + 7 + 49 - 14 √7 + 7
A = 112
B = [ 3 - 2 x ( 2/3) ⁻¹ ] ²⁰²¹
= ( 3 - 2 x 3/2 ) ²⁰²¹
= ( 3 - 6 /2 ) ²⁰²¹
= ( 3 - 3 ) ²⁰²¹ = 0
C = ( 1/4 - 3/2 ) : ( 3/4 + 1 )
= ( 1/4 - 6 /4 ) : ( 3/4 + 4/4 )
= - 5 /4 : 7 /4
= - 5 /4 x 4 /7
= - 20 /28
= - 5 /7
