Page:Calculus Made Easy.pdf/222



(for if $$y=\sin ax$$, $$\dfrac{dy}{dx} = a \cos ax$$; hence to get $$\cos ax$$ one must differentiate $$y = \dfrac{1}{a} \sin ax$$).

Try also $$\cos^2\theta$$; a little dodge will simplify matters:

hence

and

See also the Table of Standard Forms on pp. 252, 253. You should make such a table for yourself, putting in it only the general functions which you have successfully differentiated and integrated. See to it that it grows steadily!