Find f. f '(t) = 6 cos (t) + sec^2 (t), −π/2 < t < π/2, f(π/3) = 3
this requires integration
or if you don't know that word antiderivatives!
what is the antiderivative of cos(t) and sec^2(t)?
sin(t) + C and tan(t) + C
\[f'(t)=6 \cos(t)+\sec^2(t) \\ f(t)=6 \sin(t)+\tan(t)+C\] then we can agree on this right?:
now just apply f(pi/3)=3 to find C
I'm not sure how to do that
f(pi/3)=3 meants replace f(t) with 3 and replace t with pi/3
\[3=6 \sin(\frac{\pi}{3})+\tan(\frac{\pi}{3})+C\] then solve for the constant C
I got C = 0.40 (rounded to 2 decimal places)
when you solved for C?
how did you get that
yes, exact answer is -3Root3 / 2
[(-3Root3) / 2 ]+3 I meant
something looks a little fishy about that you know sin(pi/3)=sqrt(3)/2 and cos(pi/3)=1/2 so tan(pi/3)=sqrt(3) right?
\[3=6 \sin(\frac{\pi}{3})+\tan(\frac{\pi}{3}) +C \\ 3=6 \frac{\sqrt{3}}{2}+\sqrt{3}+C \\ 3=\frac{6}{2} \sqrt{3}+\sqrt{3}+C \\ 3=3 \sqrt{3}+\sqrt{3}+C\] how many sqrt(3)'s do you see on the right hand side
2
I see 4.
ah 3 + 1
\[3 \sqrt{3}+\sqrt{3} \\ \sqrt{3}+\sqrt{3}+\sqrt{3}+\sqrt{3} \\ 4 \sqrt{3}\] yep yep :)
\[3=4 \sqrt{3}+C\]
now try solving for C
-4sqrt3 + 3
tons cute :)
Now they were looking for your f that satisfied that given condition so just replace out C earlier with this number you found
our*
\[f(t)=6\sin(t)+\tan(t)+C\] that is replace this C with -4 sqrt(3)+3 and you are done
so f(x) = 6sin(t) + tan(t) + -4sqrt(3) + 3
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