How do you find the equation of the tangent line to the graph y=5^(x-2)y=5x−2 through point (2,1)?
1 Answer
Dec 13, 2016
Find the derivative of the function.
lny = ln(5^(x- 2))lny=ln(5x−2)
lny = (x- 2)ln5lny=(x−2)ln5
1/y(dy/dx) = 1(ln5) + (x- 2)01y(dydx)=1(ln5)+(x−2)0
1/y(dy/dx) = ln51y(dydx)=ln5
dy/dx = ln5/(1/y)dydx=ln51y
dy/dx= ln5(5^(x - 2))dydx=ln5(5x−2)
The slope of the tangent is therefore
y -y_1 = m(x- x_1)y−y1=m(x−x1)
y - 1 = ln5(x- 2)y−1=ln5(x−2)
y - 1= ln5x - 2ln5y−1=ln5x−2ln5
y = ln5x - 2ln5 + 1y=ln5x−2ln5+1
Hopefully this helps!