If = 20 21 , cos will be - Vidyadip

MCQ

If $\tan \theta = \frac{{20}}{{21}},$ cos$\theta$ will be

A
$ \pm \frac{{20}}{{41}}$
B
$ \pm \frac{1}{{21}}$
✓
$ \pm \frac{{21}}{{29}}$
D
$ \pm \frac{{20}}{{21}}$

✓

Answer

Correct option: C.

$ \pm \frac{{21}}{{29}}$

c
(c)$\tan \theta = \frac{{20}}{{21}} \Rightarrow \cos \theta = \pm \frac{{21}}{{29}}$.

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