How do you differentiate y=ln[x/(2x+3)]^(1/2)y=ln[x2x+3]12?

2 Answers
Jul 22, 2017

Differentiate: y=ln[x/(2x+3)]^(1/2)y=ln[x2x+3]12

Use the property ln(a^c) = (c)ln(a)ln(ac)=(c)ln(a)

y=1/2ln(x/(2x+3))y=12ln(x2x+3)

Use the property ln(a/b) = ln(a)-ln(b)ln(ab)=ln(a)ln(b)

y=1/2ln(x)-1/2ln(2x+3)y=12ln(x)12ln(2x+3)

Now, we may differentiate each term:

dy/dx=1/(2x)-1/2 2/(2x+3)dydx=12x1222x+3

dy/dx=1/(2x)-1/(2x+3)dydx=12x12x+3

Jul 22, 2017

dy/dx=3/{2x(x+3)}.dydx=32x(x+3).

Explanation:

We have, y=ln{x/(2x+3)}^(1/2).y=ln{x2x+3}12.

Using the familiar rules of Log. Fun., we get,

y=1/2ln(x/(2x+3))=1/2{lnx-ln(2x+3)}.y=12ln(x2x+3)=12{lnxln(2x+3)}.

:. dy/dx=d/dx[1/2{lnx-ln(2x+3)}].

=1/2d/dx{lnx-ln(2x+3)},

=1/2[d/dx{lnx}-d/dx{ln(2x+3)}],

=1/2[1/x-1/(2x+3)d/dx{(2x+3)}],

=1/2[1/x-2/(2x+3)],

=1/2[{(2x+3)-2x}/{x(2x+3)}],

rArr dy/dx=3/{2x(2x+3)}.