8. a) Find the differential dy of y = cos x
b) Evaluate dy for the given values of x and dx. (Round your answer to three decimal places.) x = 𝜋/3 and dx = −0.01.
for a), i got dy = - sin(x) . dx, which is correct, but I'm having issue with b). I keep getting 1.83 x 10^-4, which cannot be entered into the software, so i am really confused
5 answers
This is very weird. Not sure how to help you since 1.83*10^-4 is 0.000183 as a decimal
I just asked my teacher what to do, since i have the right answer it just won't be accepted
dy = -sin(x) dx
(b) -sin(π/3) * 0.01 = -0.00866
how did you get your result?
(b) -sin(π/3) * 0.01 = -0.00866
how did you get your result?
Ah, I see where the OP went wrong. The correct answer is supposed to be 0.009 since -sin(π/3) * -0.01 = 0.00866 ≈ 0.009
@oobleck looks like you forgot to make the differential negative
@oobleck looks like you forgot to make the differential negative
You have to be in RADIANS, not degrees
1 answer