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71 Gammes/24100g12 Isoler une variable.docx/©pa2020
Isoler une variable
Dans chacun des cas suivants, exprimer x en fonction des autres variables (a, b, c, etc.) 1) a = x b
2) a = b x 3) x b = a 4) c = ax b 5) a = b cx 6) a bx = c 7) x
a = b 8) b
ax = c 9) b
ax = d c 10) a
b x = c 11) a =
c bx d 12) a
b
x = c d 13) bx
a = d c 14) b
x a
= c 15) b
a x
= d c 16) b x
a
= c 17) b
a = d
x c 18) b x
a
= d
c
2
71 Gammes/24100g12 Isoler une variable.docx/©pa2020
Solution
1) a = x b x = a b
2) a = b x x = b a
3) x b = a x = a b
4) c = ax b x =
a b c
5) a = b cx x =
c a b
6) a bx = c x =
b c a 7) x
a = b x =
b a 8) b
ax = c x =
a bc 9) b
ax = d
c x =
ad bc 10) a
b
x = c x = b(c a)
11) a = c
bx d x =
b
c (a d)
12) a b
x = c d x =
a d c b( ) 13) bx
a = d
c x =
bc ad 14) b
x a
= c x = bc a
15) b a x
= d
c x =
d bc a
16) b x a
= c x =
c a b
17) b a =
d x c
x = c
b ad 18) b x
a
= d
c x = b
c ad
