Как представить в виде степени.. 4^5*2^21 25^13: 5^11 по действием, не понимаю эту тему,.

y`=0.8x^(-0.6)-3x^2-4x^(-5)

x=1

y`(1)=0.8-3-4=-6.2

i'm not sure that's right, but folowing my minds:

as k+k=t and t+t=k it means that t=k. so it doesn't matter what number to substitute for letters, and c=0. hope, i helped you=)