Question

Find the value of cos20 if 2 sin20 = root3

Answer 1

Solution is attached below

Answer 2

Answer:

The value of cos20 is 1/2.

Step-by-step explanation:

• We know that       $sin^{2} \alpha + cos^{2} \alpha =1$.
• So, $sin^{2} 20 + cos^{2} 20 = 1$     ...........(i)

• $2sin20 = \sqrt{3}$, $sin20 = \sqrt{3} /2$
• Putting the value of sin20 in eq. (i)

• $(\sqrt{3} /2)^{2} + cos^{2} 20 = 1$, $cos^{2} 20 = 1-3/4, cos^{2} 20 = 1/4, cos20=+1/2,-1/2$
• The value of cos20 is -1/2,+1/2

To learn more about cos:

https://brainly.in/question/48719490

To learn more about sin:

https://brainly.in/question/54171514

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