Question 841499
given that 180 degrees is equal or less than theta is less than or equals to 360 degrees, 
Note: sin is negative in the interval 180<= t <=350
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find the exact sin(t) 
if cos (t) is 
(i) 0.7
By definition, cos = x/r
Since cos(t) = 7/10, x = 7 and r = 10
The y = =sqrt[10^2-7^2] = -sqrt(51)
Your Problem:
sin(t) = -y/r = -sqrt(51)/10
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(ii) -3/5
If cos(t) = -3/5, x = -3 and r = 5
The y = -sqrt(5^2-3^2) = -sqrt(16) = -4
Your Problem:
sin(t) = y/r = -4/5
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Cheers,
Stan H.
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