Find the following a ddx x4 b ddx 9x13 c ddw 5w4 d ddx cx2 e
Find the following: a) d/dx (-x^-4) b) d/dx 9x^1/3 c) d/dw 5w^4 d) d/dx cx^2 e) d/dy aub f) d/dy - au^-b
Solution
a ) d/dx(-x-4) = - d/dx(x-4) [since,d/dx(-f(x) = -d/dx(f(x) ]
= - (-4).x-4-1 [ d/dx(xn) = nxn-1 ]
= 4x-5
b ) d/dx(9x1/3) = 9 d/dx(x1/3) [ since ,d/dx(af(x)) = a d/dx(f(x)) ]
= 9 .1/3.x(1/3)-1 [ d/dx(xn) = nxn-1 ]
= 3x-2/3
c ) d/dw(5w4) = 5d/dw(w4) [ since ,d/dw(af(w)) = a d/dx(f(w)) ]
= 5.4.w4-1 [ d/dw(wn) = nwn-1 ]
= 20w3
d ) d/dx(cx2) = c d/dx(x2) [ since ,d/dx(af(x)) = a d/dx(f(x)) ]
= c.2.x2-1 [ d/dx(xn) = nxn-1 ]
= c.2x
= 2xc
e ) d/du(aub) = ab.d/du(u)
= ab.1
= ab
