What is the equation of the tangent line of #f(x)= x^2-3x+(3x^3)/(x-7)# at # x=2#?

1 Answer

The Tangent line equation
#179x+25y=188#

Explanation:

Given #f(x)=x^2-3x+(3x^3)/(x-7)# at #x=2#

let us solve for the point #(x_1, y_1)# first

#f(x)=x^2-3x+(3x^3)/(x-7)#

At #x=2#

#f(2)=(2)^2-3(2)+(3(2)^3)/(2-7)#

#f(2)=4-6+24/(-5)#

#f(2)=(-10-24)/5#

#f(2)=-34/5#

#(x_1, y_1)=(2, -34/5)#

Let us compute for the slope by derivatives

#f(x)=x^2-3x+(3x^3)/(x-7)#

#f' (x)=2x-3+((x-7)*9x^2-(3x^3)*1)/(x-7)^2#

Slope #m=f' (2)=2(2)-3+((2-7)*9(2)^2-(3(2)^3)*1)/(2-7)^2#

#m=4-3+(-180-24)/25#

#m=1-204/25=-179/25#

The equation of the Tangent line by Point-Slope Form

#y-y_1=m(x-x_1)#

#y-(-34/5)=-179/25(x-2)#

#y+34/5=-179/25(x-2)#

#25y+170=-179(x-2)#

#25y+170=-179x+358#

#179x+25y=188#

Kindly see the graph of #f(x)=x^2-3x+(3x^3)/(x-7)# and #179x+25y=188#

Desmos.com

God bless....I hope the explanation is useful.