PUC Science Class 11 - Karnataka Board PUC Question Bank Solutions for Mathematics

If \[n = 1, 2, 3, . . . , \text{ then }  \cos \alpha \cos 2 \alpha \cos 4 \alpha . . . \cos 2^{n - 1} \alpha\] is equal to

If \[\text{ tan } x = \frac{a}{b}\], then \[b \cos 2x + a \sin 2x\]

If \[\tan\alpha = \frac{1}{7}, \tan\beta = \frac{1}{3}\], then

\[\cos2\alpha\]   is equal to

The value of `cos^2 48^@ - sin^2 12^@` is ______.

How many elements has \[P \left( A \right), \text{ if } A = \phi\]