Advertisements
Advertisements
Question
Solve the following:
log (x + 1) + log (x - 1) = log 48
Solution
log (x + 1) + log (x - 1) = log 48
⇒ log {(x + 1)(x - 1)} = log 48
⇒ log (x2 - 1) = log 48
⇒ x2 - 1 = 48
⇒ x2 = 49
⇒ x = 7 ...(neglecting the negative value).
APPEARS IN
RELATED QUESTIONS
If log`( a - b )/2 = 1/2( log a + log b )`, Show that : a2 + b2 = 6ab.
If p = log 20 and q = log 25 , find the value of x , if 2log( x + 1 ) = 2p - q.
Given log10x = 2a and log10y = `b/2`. Write 102b + 1 in terms of y.
Solve for x, if : logx49 - logx7 + logx `1/343` + 2 = 0
Solve the following:
log 7 + log (3x - 2) = log (x + 3) + 1
Solve for x: `("log"121)/("log"11)` = logx
Solve for x: `("log"1331)/("log"11)` = logx
Solve for x: `("log"289)/("log"17)` = logx
If log x = a and log y = b, write down
102b in terms of y
Prove that log (1 + 2 + 3) = log 1 + log 2 + log 3. Is it true for any three numbers x, y, z?