Question

c.1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256

d.5,7x 16,2+3,7-6,2x 4,8-6,2x4,6/13,4+12,3+11,2

Answer 1

\(c.\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{16}+\dfrac{1}{32}+\dfrac{1}{64}+\dfrac{1}{128}+\dfrac{1}{256}\)

\(=1-\dfrac{1}{2}+\dfrac{1}{2}-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{8}+\dfrac{1}{8}-\dfrac{1}{16}+\dfrac{1}{16}-\dfrac{1}{64}+\dfrac{1}{64}-\dfrac{1}{128}+\dfrac{1}{128}-\dfrac{1}{256}\)

\(=1-\dfrac{1}{256}=\dfrac{255}{256}.\)