Question

according to the first trinometical indentity
sin square theta + cos square theta =1


so can we use this identity in this question?
if yes then why
if no then why no?


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Answer 1

Answer:

If you know the value then directly put them in the question and solve

Answer 2

$\bigstar \: \boxed{\sf{\color{Lime}{Answer:}}}$

We know that cos 30° = √3/2

⇨ cos2 30° = 3/4 cos 60° = 1/2

⇨ cos2 60° = 1/4 sec 30° =(2/√3)

⇨ sec2 30° = 4/3 tan 45° = 1

⇨ tan2 45° = 1 sin 30° = 1/2

⇨ sin2 30° = 1/4 Now, (5cos260+4sec230°-tan245°)

(sin230°+cos230°)

Edit :- To read the full solution scroll right to left it would be easy.

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