Prove this logarithm equation

60 Views Asked by At

I keep getting the wrong answer. Can someone please correct my working out

enter image description here

  • a^x=b^(1-x)
  • In(a)^x=In(b)^(1-x)
  • xIn(a)=(1-x)In(b)
  • xIn(a)=In(e)-xIn(b)
  • xIn(a)+xIn(b)=In(e)
  • x[In(a)+In(b)]=Ine
  • x=In(e)/[(In(a)+In(b)]

the correct answer is In(b)/(In(a)+In(b)

1

There are 1 best solutions below

3
On

How have you find $\displaystyle \ln e?$

Applying logarithm wrt $e$ on $\displaystyle a^x=b^{1-x}$

we get $$ x\ln a=(1-x)\ln b\implies x(\ln a+\ln b)=\ln b$$