## Yahoo! 3 years ago Find the Period of $2 cos^3 x + 5cos4x$

1. Ishaan94

$$\cos^3x$$'s period is $$2\pi$$ and $$\cos 4x$$'s period is $$\pi/2$$. The period for the given equations should be $$2\pi$$.

2. Ishaan94

equation*

3. Yahoo!

lol....u seems to find the answer easily

4. Yahoo!

any trick behind that

5. Ishaan94

Practice. :-)

6. Yahoo!

in my...book the soln is given half a page

7. Yahoo!

@Ishaan94 hw cos^3 x period is 2 pie

8. Ishaan94

Try plotting $$\cos^3x$$. You will see it yourself or you can prove it as well.

9. Yahoo!

Is this +2 's topic

10. Ishaan94

idk. but you it's pretty basic you can learn it even class 10th.

11. Ishaan94

you know* ...

12. Yahoo!

lol...not in 10 th....

13. Ishaan94

yes. you can. :-)

14. Yahoo!

thxxxx