bonjour
1 . 40 x 1.5 = 60
2 . 68.50 : 1.5 = 45 .6 L environ
3 . f (x) = 1.5 x
ensemble def = [ 4 ; 90 ]
fonction linéaire
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f (x ) = x² + 5
f ( 1) = 1 + 5 = 6
f ( - 2 ) = 4 + 5 = 9
f ( √2) = 2 + 5 = 7
f ( - √3) = 3 + 5 = 8
x² + 5 = 5
x² = 0
x = 0
x² + 5 = 9
x² = 4
x = √4 ou - √4
x = 2 ou - 2
x² + 5 = 30
x² + 5 - 30 = 0
x² - 25 = 0
( x - 5 ) ( x + 5 ) = 0
x = 5 ou - 5
