tangent line equation
Hey, im having some problems with this
Find the equation of the line tangent to the curve y=2x^4-x^3 at the point (-1, 3). Any help appreciated.
i plugged the ordered pair into the genreal equation of a line, and now im stuck. What would the dy/dx for y=2x^4-x^3 be?
any help appreciated, thanks
You just wanna find the derivative of the original function...
So if then
Use the x value you were given in the point (-1,3) and you will get that
So, now that you have a slope and a point, you can find the slop of the line by using the formula So you get the equation of the line to be
wait, shouldnt the final answer be y=-11x-8
Actually...on second thought...I mixed up my numbers a little bit there
It should be
when i plug this into my calculator it doesnt even touch the parabola. isnt the answer supposed to be y=-11x-8, thats what i got when I solved and thats what the calc is saying for a tangent line to the parabola at X=-1
Originally Posted by Kalter Tod
Haha yeah it is...Apparently, I can't add numbers.
I did it all in my head, so sorry for the math mistakes haha