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Logarithm Equation
- Question 1
- If log1625 = xlog25 then x equals
- Solution
- Let y = log1625 = xlog25
- when y = log1625
- then 16y = 25
- then (24)y = 52
- then (2y)4 = 52 ...equation (1)
- when y = xlog25
- then y = log25x
- then 2y = 5x ...equation (2)
- Substitute the expression for 2y in equation (2) into equation (1)
- (5x)4 = 52
- then 54x = 52 then 4x = 2 then x = 1/2