Réponse :
Explications étape par étape
Bonjour
Exercice 1 : Isoler a, b, c, d.
a c
--- = ---
b d
a = b x c / d
a = bc / d
b = ad / c
c = ad / b
d = bc / a
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Exercice 2 : Isoler a,b,c,d,e,f,g,h
ab ef
---- = ----
cd gh
a = cdef / bgh
b = cdef / agh
c = abgh / def
d = abgh / cef
e = abgh / cdf
f = abgh / cde
g = cdef / abh
h = cdef / abg
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Exercice 3 : Isoler a,b,c,d,e,f,g,h
a+b e+f
----- = -----
c+d g+h
a + b = (e + f)(c + d) / (g + h)
a = (e + f)(c + d) / (g + h) - b
b = (e + f)(c + d) / (g + h) - a
c + d = (a + b)(g + h) / (e + f)
c = (a + b)(g + h) / (e + f) - d
d = (a + b)(g + h) / (e + f) - c
e + f = (a + b)(g + h) / (c + d)
e = (a + b)(g + h) / (c + d) - f
f = (a + b)(g + h) / (c + d) - e
g + h = (e + f)(c + d) / (a + b)
g = (e + f)(c + d) / (a + b) - h
h = (e + f)(c + d) / (a + b) - g
