Recognize logarithm of 1: We are asked to find the value of the logarithm of 321 with base 8. The first step is to recognize that the logarithm of 1 to any base is 0, because any number to the power of 0 is 1.log8(1)=0
Express 321 as a power of 8: Now we need to consider the 321 part. We can express 32 as a power of 8 to use the quotient property of logarithms, which states that the logarithm of a quotient is the difference of the logarithms.32 can be written as 25, and since 8 is 23, we can rewrite 32 as 80.
Simplify the expression: Using the property of exponents (ab)c=a(b∗c), we can simplify (23)35 to 2(3∗35), which simplifies to 25, confirming our previous statement that 32 is 25.
Write as difference of logarithms: Now we can write the original expression as the difference of two logarithms:log8(1)−log8(32)Since we already know log8(1)=0, we only need to evaluate log8(32).
Express 32 as a power of 8: We can express 32 as 8 to the power of some number. Since 8 is 23 and 32 is 25, we can find the exponent by solving for x in 8x=32.80
Solve for the exponent: Solving the equation 3x=5 gives us x=35. Therefore, 32 is 8 to the power of 35, and we can write:log8(32)=log8(835)
Apply power property of logarithms: Using the power property of logarithms, which states that logb(ac)=c⋅logb(a), we get:log8(835)=35⋅log8(8)
Evaluate log8(8): Since the logarithm of a number to the same base is 1, log8(8)=1. Therefore:35⋅log8(8)=35⋅1=35
Combine results to find the value: Now we can combine our results to find the value of the original expression: log8(321)=log8(1)−log8(32)=0−35=−35
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