The value of cos2 45° – sin2 45° is: (a) \(\frac{\sqrt{3}}{2}\)(

1.	The value of cos2 45° – sin2 45° is: (a) \(\frac{\sqrt{3}}{2}\)(b) \(\frac{1}{2}\)(c) 0 (d) \(\frac{1}{\sqrt{2}}\)
Answer» (c) 0 cos² 45° – sin² 45° = cos 2 x 45° (∵ cos² A – sin² A = cos 2A) = cos 90° = 0

The value of cos2 45° – sin2 45° is: (a) \(\frac{\sqrt{3}}{2}\)(b) \(\frac{1}{2}\)(c) 0 (d) \(\frac{1}{\sqrt{2}}\)

Answer»

(c) 0

cos² 45° – sin² 45°

= cos 2 x 45° (∵ cos² A – sin² A = cos 2A)

= cos 90°

= 0