7^(-2) is too small as compared to 7^6 that its addition to 7^6 doesn't make any remarkable difference to its value, hence {7^(-2)+7^6} divided by 7^4 will be equivalent to 7^6 divided by 7^4, the result equals [spoiler]7^2 or 49[/spoiler].ern5231 wrote:{7^(-2)+7^6} divided by 7^4
62) What would be a quick way of doing this?
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sanju09
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analyst218
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or you could justern5231 wrote:{7^(-2)+7^6} divided by 7^4
[7^4(7^-2 + 7^2)] /7^4 = 7^-2 + 7^2 = 49.0..
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jeffedwards
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Start out by simplifying
When you divide a number raised to a number by another number raised to another number with the same base (I hope you followed that),you just subtract the powers.
Let's reduce as follows:
(7^(-2)+7^6) / 7^4
7^(-2 - 4)+7^(2 - 4)
7^(-6)+7^2
Now think a little more
7^(-6) is the same as 1/(7^6)
Add that to 49...so your just a little above 49...
When you divide a number raised to a number by another number raised to another number with the same base (I hope you followed that),you just subtract the powers.
Let's reduce as follows:
(7^(-2)+7^6) / 7^4
7^(-2 - 4)+7^(2 - 4)
7^(-6)+7^2
Now think a little more
7^(-6) is the same as 1/(7^6)
Add that to 49...so your just a little above 49...
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sanju09
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are you sure with what's in bold? rest is greatanalyst218 wrote:or you could justern5231 wrote:{7^(-2)+7^6} divided by 7^4
[7^4(7^-2 + 7^2)] /7^4 = 7^-2 + 7^2 = 49.0..
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
