Q3.If a^x= b^y= c^z and b^2 =
= ac,
Prove that: y= 2xz/x+z
Answers
Given :
a^x = b^y = c^z , b² = ac
To prove :
y = 2xz/(x + z)
Proof :
Let
a^x = b^y = c^z = k
Thus ,
• If a^x = k , then a = k^(1/x)
• If b^y = k , then b = k^(1/y)
• If c^z = k , then c = k^(1/z)
Also ,
It is given that , b² = ac
=> [ k^(1/y) ]² = [ k^(1/x) ]•[ k^(1/z) ]
=> k^(2/y) = k^(1/x + 1/z)
=> 2/y = 1/x + 1/z
=> 2/y = (z + x)/xz
=> y = 2xz/(x + z)
Hence proved .
Step-by-step explanation:
let a^x=b^y=c^z= k'
where k and k' are constants and >0
a^x= k'
x log a = k
log a = k/x -----A
b^y = k'
y log b=k
log b = k/y -----B
c^z=k'
z log c =k
log c = k/z ------C
b^2=ac
2log b = log ac
(logmn=logm+logn)
2log b = loga+logc ------D
substitute from A,B,C in D
2k k k
__ = __+__
y x z
divide the above equation with k on both sides
2 1 1
__ = __+ __
y x z
2 z + x
__ = ______
y xz
cross multiply
2xz = y(x+z)
y=2xz/(x+z)
hope this helps