Question

B- 2a/( a-b)∙(a^2-b^2)/4a при a=2, b=1

Answer 1

$\frac{b-2a}{ \frac{(a-b)*(a^{2}- b^{2})}{4a}}$, при a=2, b=1 ⇒

$\frac{1-2*2}{ \frac{(2-1)*(2^{2}- 1^{2})}{4*2} }$ = $\frac{1-4}{ \frac{(1)*(4-1)}{8} }$ =  $\frac{-3}{ \frac{1*3}{8} }$ = $- \frac{3}{ \frac{3}{8} }$ = $- \frac{1}{ \frac{1}{8} }$ = $-\frac{1}{8}$