How do you implicitly differentiate sqrt(xy) = x-y/(x-1)xy=xyx1?

1 Answer
Jul 27, 2018

(dy)/(dx)=(2sqrt(xy)(x-1)^2+2ysqrt(xy)-y(x-1)^2)/((x^2-x+2sqrt(xy))(x-1))dydx=2xy(x1)2+2yxyy(x1)2(x2x+2xy)(x1)

Explanation:

Here ,

sqrt(xy)=x-y/(x-1)xy=xyx1

Diff. each term w.r.t. xx, (using product,quotient and chain rules)

1/(2sqrt(xy))*d/(dx)(xy)=1-((x-1)y_1-y(1))/(x-1)^212xyddx(xy)=1(x1)y1y(1)(x1)2

=>1/(2sqrt(xy))[xy_1+y*1]=1-y_1/(x-1)+y/(x-1)^212xy[xy1+y1]=1y1x1+y(x1)2

=>(xy_1)/(2sqrt(xy))+y/(2sqrt(xy))=1-y_1/(x-1)+y/(x-1)^2xy12xy+y2xy=1y1x1+y(x1)2

=>(xy_1)/(2sqrt(xy))+y_1/(x-1)=1+y/(x-1)^2-y/(2sqrt(xy))xy12xy+y1x1=1+y(x1)2y2xy

y_1{x/(2sqrt(xy))+1/(x-1)}=(2sqrt(xy)(x-1)^2+2ysqrt(xy)-y(x- 1)^2)/(2sqrt(xy)(x-1)^2)y1{x2xy+1x1}=2xy(x1)2+2yxyy(x1)22xy(x1)2

y_1{(x^2-x+2sqrt(xy))/(2sqrt(xy)(x-1))}y1{x2x+2xy2xy(x1)}=(2sqrt(xy)(x- 1)^2+2ysqrt(xy)-y(x-1)^2)/(2sqrt(xy)(x-1)^2)2xy(x1)2+2yxyy(x1)22xy(x1)2

y_1(x^2-x+2sqrt(xy))=(2sqrt(xy)(x-1)^2+2ysqrt(xy)-y(x-1)^2)/((x-1))y1(x2x+2xy)=2xy(x1)2+2yxyy(x1)2(x1)

:.y_1=(2sqrt(xy)(x-1)^2+2ysqrt(xy)-y(x-1)^2)/((x^2-x+2sqrt(xy))(x-1))

Where, y_1=(dy)/(dx)