Question

Find the f(a) at the given value of a for each function y=f(x)
[Finding the Equation of a Tangent Line]

f(x)=8x-3; a=2

I’m suppose to use lim x—>2 to solve this I think

Answer 1

I don’t know how to solve using lim but is this correct?
y=8(2)-3
Y=16-3
Y=13
d/dx [8x]+ d/dx [-3]
8+d/dx [-3]
8+0
8
y-(13)=8•(x-2))
y-13=8•(x-2)
y=8x-3

Answer 2

no calculus needed here.
8x-3 is a linear function, with a constant slope of 8
There is no tangent line, except the line itself!

VERY poor excuse for an exercise in limits and tangents.