It is not a matter of "choosing" here, you must calculate it.
f ' (x) = cos(7-5x)(-5)
= -5cos(7-5x)
f '(π)
= -5cos(7-5π)
= 5cos(-8.7078..) = 3.770
Did you set your calculator to radians in your DRG mode ?
If f(x) = sin(7 − 5x), find f′(π), which is the derivative at π:
−0.754
−0.657
0
0.657
3.770
I chose 0.657 ... I did not really get this exact answer, its just that while I was trying to figure this out my answer was actually 0.6978 but I just kind of assumed it was D...So did I get this right?
2 answers
Ha.. I was just using a old fashion calculator and hoping I could do the rest in my head. But thanks I think I understand now. =D
1 answer