Q.45 The value of \(\log_n 4 – 16\) is \(-32\). The value of \(n\) is _________.
logn(4-16) = -32 is 2.
Question and given condition
The question states: “The value of logn 4-16 is -32. Find the value of n.”
In mathematical form, this is written as:
logn(4-16) = -32.
Step-by-step detailed solution
1. Convert logarithmic form to exponential form
By definition of a logarithm, if loga b = c, then ac = b.
Applying this to logn(4-16) = -32 gives:
n-32 = 4-16.
2. Remove the negative exponents
Rewrite both sides with positive exponents:
n-32 = 4-16 ⇒ 1 / n32 = 1 / 416.
Since the fractions are equal, the denominators must be equal, so
n32 = 416.
3. Express 4 as a power
Note that 4 can be written as 22, and hence
416 = (22)16 = 232.
Therefore, we have n32 = 416.
4. Match exponents to find n
Observe that 416 is the same as (41)16, and we already have
n32 on the left side. To compare exponents conveniently, take both sides to the
power 1⁄16:
(n32)1/16 = (416)1/16, which yields
n2 = 4.
Solving n2 = 4 gives n = ±2, but the base of a logarithm must be positive and not equal to 1.
Therefore, the valid value is n = 2.
5. Verification of the solution
Substitute n = 2 back into the original equation:
log2(4-16) =
log2((22)-16) =
log2(2-32) = -32.
This matches the given value, confirming that n = 2 is correct.
Final answer
The base n that satisfies logn(4-16) = -32 is:
n = 2


