Exponent, massive numbers

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Exponent, massive numbers

by Kaunteya » Sat Mar 01, 2008 11:08 am
99,999^2 - 1^2 =

A. (10^10) - 2
B. ((10^5) – 2)^2
C. 10^4((10^5) – 2)
D. 10^5((10^4) – 2)
E. 10^5((10^5) – 2)

I don't know.

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Re: Exponent, massive numbers

by nqhussain » Sat Mar 01, 2008 11:38 am
Kaunteya wrote:99,999^2 - 1^2 =

A. (10^10) - 2
B. ((10^5) – 2)^2
C. 10^4((10^5) – 2)
D. 10^5((10^4) – 2)
E. 10^5((10^5) – 2)

I don't know.
Answer:

99,999^2 - 1^2=(100K-1)^2 - 1^2= 100k*100k-100k-100k+1-1=
10^5*10^5-2*10^5=10^5(10^5-2)

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by Kaunteya » Sat Mar 01, 2008 11:46 am
Now I got it. Basically it a (x + y)(x - y) question.