Q9 of 80 Page 311

Let us fill in the blanks :

i. The value of is ________.


ii. If then the value of cos θ is __________


iii. If then the value of cos4θ – sin4θ is __________

(i) Given,


⇒


=


= 4


(ii) Given,


⇒ θ = 0


⇒ cos0° = 1


(iii) Given,


⇒ cos4θ –sin4θ = (cos2θ –sin2θ)(cos2θ + sin2θ)


=


=


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