Question

x^2/ x^2+2x+1 - x-1/x+1 , при x= 19
найдите значение рационального выражения

Answer 1

x²+2x+1=(x+1)²
(x²/(x+1)²) - (x-1)/(x+1)=
=(x²-(x-1)(x+1))/(x+1)²=
=(x²-x²+1)/(x+1)²=1/(x+1)²=
=1/(19+1)²=1/20²=1/400=
=0.0025