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Given Log3=0.4772, log7=0.8451, log5=0.6990, log2=0.3010, how do you evaluate Log21?

Answer 1

Serenity Johnson

#1.3223#

#\Log(21)#

#=\log(3\times 7)#

#=\log3+\log7#

#=0.4772+0.8451#

#=1.3223#

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Answer 2

Elias Ackerman

To evaluate Log21, you can use the properties of logarithms. Logarithms follow the property that the logarithm of a product is equal to the sum of the logarithms of the factors. Similarly, the logarithm of a quotient is equal to the difference of the logarithms of the numerator and the denominator.

Therefore, Log21 can be evaluated by expressing 21 as a product or quotient of numbers with known logarithms. Since 21 can be expressed as the product of 3 and 7 (21 = 3 * 7), we can use the property of logarithms to evaluate Log21.

Log21 = Log(3 * 7) = Log3 + Log7.

Given that Log3 = 0.4772 and Log7 = 0.8451, we can substitute these values into the equation:

Log21 = Log3 + Log7 = 0.4772 + 0.8451 = 1.3223.

Therefore, Log21 is approximately equal to 1.3223.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.