MATHEMATICS

JAMB 2021 - Question 5

Mathematics 2021 JAMB Past Questions - Question 5: If log 7.5 = 0.8751, evaluate 2 log 75 + log 750.

If log 7.5 = 0.8751, evaluate 2 log 75 + log 750.
A:
B:
C:
D:
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Correct Answer

C

Explanation

To evaluate the expression 2 log 75 + log 750, we can use the properties of logarithms.Given that log 7.5 = 0.8751, we can rewrite 75 and 750 in terms of 7.5:75 = 7.5 * 10750 = 7.5 * 100Now, let's substitute these values into the expression:2 log 75 + log 750 = 2 log (7.5 * 10) + log (7.5 * 100)Using the logarithmic property log(ab) = log(a) + log(b), we can simplify the expression:2 log (7.5 * 10) + log (7.5 * 100) = 2 (log 7.5 + log 10) + (log 7.5 + log 100)Since log 10 = 1 and log 100 = 2, we can substitute these values:2 (log 7.5 + log 10) + (log 7.5 + log 100) = 2 (0.8751 + 1) + (0.8751 + 2)Simplifying further:2 (0.8751 + 1) + (0.8751 + 2) = 2.7502 + 3.8751Adding the terms:2.7502 + 3.8751 = 6.6253Therefore, the value of 2 log 75 + log 750 is approximately 6.6253.