Giải thích các bước giải:
$\text{A,⇒3A=1+1/2+1/4+1/8+1/16+1/32}$
$\text{⇒3A=1+1−1/2+1/2−1/4+1/4−1/8+1/8−1/16+1/16−1/32}$
$\text{⇒3A=1+1−1/32}$
$\text{⇒3A=2−1/32}$
$\text{⇒A=(2−1/32):3=21/32}$
$\text{B,(1+3+5+7......+2011+2013) × (125 × 125 × 127 -127 × 127 × 125)}$
$\text{⇒(1+3+5+7......+2011+2013) × (15 498 - 15 498)}$
$\text{⇒(1+3+5+7......+2011+2013) × 0}$
$\text{⇒0}$
Xin tus ctlhn! 🥰