If log (a+b2)=12(log a+log b) , show that 12(a+b)=ab\log \space \Big(\dfrac{a + b}{2}\Big) = \dfrac{1}{2} (\log \space a + \log \space b)\text{ , show that }\dfrac{1}{2} (a + b) = \sqrt{ab}log (2a+b)=21(log a+log b) , show that 21(a+b)=ab.
1 Like
Given,
⇒log (a+b2)=12(log a+log b)⇒log (a+b2)=12log ab⇒log (a+b2)=log ab12⇒(a+b2)=ab12⇒12(a+b)=ab.\Rightarrow \log \space \Big(\dfrac{a + b}{2}\Big) = \dfrac{1}{2} (\log \space a + \log \space b) \\[1em] \Rightarrow \log \space \Big(\dfrac{a + b}{2}\Big) = \dfrac{1}{2} \log \space ab \\[1em] \Rightarrow \log \space \Big(\dfrac{a + b}{2}\Big) = \log \space {ab} ^{\dfrac{1}{2}} \\[1em] \Rightarrow \Big(\dfrac{a + b}{2}\Big) = {ab} ^{\dfrac{1}{2}} \\[1em] \Rightarrow \dfrac{1}{2} (a + b) = \sqrt{ab}.⇒log (2a+b)=21(log a+log b)⇒log (2a+b)=21log ab⇒log (2a+b)=log ab21⇒(2a+b)=ab21⇒21(a+b)=ab.
Hence, proved that 12(a+b)=ab\dfrac{1}{2} (a + b) = \sqrt{ab}21(a+b)=ab.
Answered By
Show that log (1 + 2 + 3) = log 1 + log 2 + log 3.
If log (m + n) = log m + log n, show that m=nn−1m = \dfrac{n}{n - 1}m=n−1n.
Solve for x :
log (x + 2) + log (x − 2) = log 5
log (x + 4) − log (x − 4) = log 2