MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Higher Order Derivatives

Solve the fol...

Question

Solve the following equation:
$cos 2 x cos x = sin 7 x sin 6 x + 5 cos \frac{π}{2}$

Open in App

Solution

$cos 2 x cos x = sin 7 x sin 6 x + 5 cos \frac{π}{2}$
$cos (3 x) + cos x = cos x - cos 13 x$
$cos 3 x + cos 13 x = 0$
$2 cos 8 x cos 5 x = 0$
Either, $cos 8 x = 0, 8 x = (2 n + 1) \frac{π}{2}, x = (2 n + 1) \frac{π}{16} .$
or, $cos 5 x = 0, 5 x = (2 n + 1) \frac{π}{2}, x = (2 n + 1) \frac{π}{10} .$

Suggest Corrections

thumbs-up

0

Similar questions

Q. Solve the following equations.

s i n \frac{x}{2} c o s 2 x + s i n^{2} x c o s \frac{x}{2} = c o s^{2} x c o s \frac{x}{2} .

\frac{sin 8 x cos x - sin 6 x cos 3 x}{cos 2 x cos x - sin 3 x sin 4 x} = tan 2 x

cos 2 x cos \frac{x}{2} - cos 3 x cos \frac{9 x}{2} = sin 5 x sin \frac{5 x}{2}

\int \frac{\cos 2 x}{{(\cos x + \sin x)}^{2}} d x

Q. Solve the following equation:

sin x = \frac{\sqrt{2}}{2} .

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Higher Order Derivatives

MATHEMATICS

Watch in App

explore_more_icon

Explore more

Higher Order Derivatives

Standard XII Mathematics

Join BYJU'S Learning Program

CrossIcon