dx=d(4x-5)/4
∫^(1)_(0)(4x-5)^4dx= ∫^(1)_(0)(4x-5)^4d(4x-5)/4=
=(1/4)*(4x-5)^5/5|^(1)_(0)=(1/20)* [b]([/b](4*1-5)^5-(4*0-5)^5 [b])[/b]=
=(1/20)*(-1+5^5)=3124/20=781/5= [b]156,2[/b]
∫ ^(π/2)_(0)sin(x/2)dx=2 ∫ ^(π/2)_(0)sin(x/2)d(x/2)=
=2*cos(x/2)|^(π/2)_(0)=
=2cos(π/4)-2cos0=2sqrt(2)/2 - 2 = [b]sqrt(2)-2[/b]