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* veut dire fois (x)
1|a) 100-10*(2+2*3)+20 = 100-10*(2+6)+20
= 100-10*8+20
= 100-80+20
= 20+20
= 40
b)1) 8+2 * x = 8+2x
2) 3*x*5-x*3*x = (3*5*x)-(x*x*3)
= (15x)-(3x²)
= -3x²+15x
c) (x²-2)(2x+3) = (3²-2)(2*3+3)
= (9-2)(6+3)
= 7*9
= 63
* veut dire fois (x)
1|a) 100-10*(2+2*3)+20 = 100-10*(2+6)+20
= 100-10*8+20
= 100-80+20
= 20+20
= 40
b)1) 8+2 * x = 8+2x
2) 3*x*5-x*3*x = (3*5*x)-(x*x*3)
= (15x)-(3x²)
= -3x²+15x
c) (x²-2)(2x+3) = (3²-2)(2*3+3)
= (9-2)(6+3)
= 7*9
= 63