Question

sec squared theta (1 + sec 2 theta ) = 2 sec 20​

Answer 1

Answer:

Let theta be x.

${sec}^{2} x(1 + sec2x) \\ = {sec}^{2}x(1 + \frac{1 + {tan}^{2}x }{1 - {tan}^{2}x } ) \\ = (1 + {tan}^{2} x)( \frac{1 - {tan}^{2} x + 1 + {tan}^{2} x}{1 -{tan}^{2} x } ) \\ = (1 + {tan}^{2} x)( \frac{2}{1 - {tan}^{2} x } ) \\ = 2sec2x \\ hence \: proved$

Answer 2

Answer:

this is correct..........................