SOLUTION: 2^(x-1)+2^(x-1)=2860 find the value of x ? (Surds and indices)

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Question 895141: 2^(x-1)+2^(x-1)=2860 find the value of x ? (Surds and indices)
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
2^(x-1) + 2^(x-1) = 2*2^(x-1)

your formula becomes:

2*2^(x-1) = 2860

divide both sides by 2 to get:

2^(x-1) = 1430

take log of both sides to get:

log(2^(x-1) = log(1430

since log(2^(x-1)) = (x-1)*log(2), your equation becomes:

(x-1)*log(2) = log(1430)

divide both sides by log(2) to get:

x-1 = (1og(1430)/log(2)

add 1 to both sides to get:

x = log(1430)/log(2) + 1

solve for x to get x = 11.48179...

confirm by going back to the original equation to get:

2^(11.28179... - 1) + 2^(11.28179... - 1) = 2860

solve to get:

2860 = 2860.

your answer is that x = 11.48179943...

the value for x was internally stored in my calculator.

all calculations were done using the stored number.