which of the following is equal to (2^k)(5^k-1)?
A.2^(10^k-1)
B.5^(10^k-1)
C.10^k
D.2(10^k)
E.10^2k-1
OA E
(2^k)(5^k-1)=?
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In the final step he multiplied both numerator and denominator by 2bhumika.k.shah wrote:sowree
the OA is A
how did you get the final step ? where did the 2 come from?
= 10^k/5
=2*10^k/(2*5)
=2*10^k/10
=2*10^k-1
RAM SHARMA
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diegow77 wrote:ramsharma,
I don't get how you come from 10^k/5 to 2*10^k-1 can you explain in more details.
= 10^k/5
=2*10^k/(2*5) -multiplied numerator and denominator by 2(eg 3/5=2*3/5*2)
=2*10^k/10 -Denominator(2*5=10),Numerator remains as it is(eg 3/5=2*3/5*2=2*3/10)
=2*10^k-1 (10^k/10=10^k-1 eg.10^11/10=10^(11-1)
Hope you will get now
RAM SHARMA