imaan2121
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2^x=7
so I typed into the calculator log base 2 7 = 2.8
However, on the answers, it says it should be done like this:
log2^x=log7
xlog2=log7
x=log7/log2 = 0.356
How does this make sense as when I type 2^0.356 into the calculator, the answer is 1.28
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CIEBioloysifh
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You've typed it into the calculator wrong, log7/log2 = 2.807..
Check again.
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_gcx
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(Original post by imaan2121)
2^x=7
so I typed into the calculator log base 2 7 = 2.8
However, on the answers, it says it should be done like this:
log2^x=log7
xlog2=log7
x=log7/log2 = 0.356
How does this make sense as when I type 2^0.356 into the calculator, the answer is 1.28
You worked out \frac{log 2}{log 7}. Errors like this should be pretty blatant, as you're expecting a result over 2 (as 2^2=4), and less than 3 (as 2^3=8). In fact, an exponent below 1 would mean that the result would be under 2. Keep this in mind
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imaan2121
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(Original post by _gcx)
You worked out \frac{log 2}{log 7}. Errors like this should be pretty blatant, as you're expecting a result over 2 (as 2^2=4), and less than 3 (as 2^3=8). In fact, an exponent below 1 would mean that the result would be under 2. Keep this in mind
Yeah, that's what I thought, but the answers say log2/log7?
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_gcx
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(Original post by imaan2121)
Yeah, that's what I thought, but the answers say log2/log7?
They are incorrect, unless you meant 7^x = 2.
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Zacken
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(Original post by imaan2121)
2^x=7
so I typed into the calculator log base 2 7 = 2.8
However, on the answers, it says it should be done like this:
log2^x=log7
xlog2=log7
x=log7/log2 = 0.356
How does this make sense as when I type 2^0.356 into the calculator, the answer is 1.28
(Original post by imaan2121)
Yeah, that's what I thought, but the answers say log2/log7?
You've said contradictory things here...
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