If f(x) = log10 (1 + x), then what is 4f(4) + 5f(1) – log10 2 equal to?
If f(x) = log10 (1 + x), then what is 4f(4) + 5f(1) – log10 2 equal to? Correct Answer 4
Calculation:
Given: f(x) = log10 (1 + x)
⇒ f(4) = log10 (5)
⇒ f(1) = log10 (2)
⇒ 4f(4) + 5f(1) – log10 2 = log10 625 + log10 32 - log10 2
⇒ 4f(4) + 5f(1) – log10 2 = log10 (625 × 32) - log10 2
⇒ 4f(4) + 5f(1) – log10 2 = log10 (2 × 104) - log10 2
⇒ 4f(4) + 5f(1) – log10 2 = log10 2 + 4 log10 10 - log10 2
⇒ 4f(4) + 5f(1) – log10 2 = 4
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Feb 20, 2025