SOLUTION: Find the exact value of (sinB)^2 when cosB= 2/5

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Question 628989: Find the exact value of (sinB)^2 when cosB= 2/5
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
sin^2 + cos^2 = 1

sin^2 + (2/5)^2 = 1

sin^2 + 4/25 = 1

sin^2 = 1 - 4/25

sin^2 = 25/25 - 4/25

sin^2 = 21/25

So the answer is 21%2F25

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