Question

Cum se calculeaza suma 1+ 2 la -1 +2 la -2 +2 la -3?

Answer 1

1+2⁻¹+2⁻²+2⁻³=

=1+1/2+(1/2)²+(1/2)³=

=1+1/2+1/4+1/8=

=8/8+4/8+2/8+1/8=

=12/8+2/8+1/8=

=14/8+1/8=15/8

Answer 2

Răspuns:

$\displaystyle\bf\ 1 + 2^{-1} +2^{-2} +2^{-3} =\\\\ 1 + \frac{1}{2^{1} } +\frac{1}{2^{2} } +\frac{1}{2^{3} } =\\\\\frac{1}{1} +\frac{1}{2}+\frac{1}{4}+\frac{1}{8}=\\\\\frac{8+4+2+1}{8} =\boxed{\frac{15}{8} }$