-6(-а+3b)+4(-2-b)=
6а - 18b -8а -4b
-2а+22
При а = — 1/4 , при b= — 3/22
-2*(-1/4)+ 22*(-3/22)=
-5/2
f(x)' = (x^2/2x-1)' = ( (x^2)' (2x-1) -x^2*(2x-1)' ) / (2x-1)^2 =
= ( 2x (2x-1) - x^2*2 ) / (2x-1)^2 = ( 4x^2 -2x - 2 x^2 ) / (2x-1)^2 =
= ( 2x^2 -2x ) / (2x-1)^2 = 2x( x -1 ) / (2x-1)^2
8√5x+3*4√5x-7*0,1√5x=8√8x+12√5x-0,7√5x=19,3√5x