Dr. J's Maths.com
Where the techniques of Maths
are explained in simple terms.

Trigonometric functions - Calculus - Differentiate ... hence find.
Test Yourself 1.


 

The questions on this page all require you:

1. to differentiate the first equation/expression; and

2. to use the results of that differentiation to determine the integral of another.

  1. (i) Differentiate x cosx.

(ii) Hence evaluate

.

Answer.I = 1.
2. (i) Differentiate y = x2 + 1.

(ii) Hence find .

  3. (i) Differentiate sinx - x cos x.

(ii) Hence find .

Answer.I = 1.
4. By differentiating y = cos x, find

.

  5. 6.
 

7. Use the trigonometry identity to show that

8. (i) Differentiate y = x tan x.

(ii) Hence find an expression for

(also using the results of Q7).

  9. (i) Differentiate

.

(ii) Hence find

.

Answer.-3/4.
10. (i) Differentiate cos2(3x) with respect to x.

(ii) Hence evaluate

.

Answer.(ii) Integral - 2.
  11. 12.
  13. (i) Show that

tan3 x = tan x sec2 x - tanx

(ii) Hence find

14.
Applications 15. (i) Differentiate sin (x2).

(ii) Use this result to find the exact area bounded by y = xcos (x2), the x axis and the lines x = 0 and x = 1.

  16. (i) By expressing cot x as prove that .

(ii) Find the area of the region bounded by the curve y = cosec2 x, the x axis and the lines π/6 and x = π/3.