SOLUTION: Hello tutor, how do I solve the following trig function using the Factor Formula method, where theta is between -90degrees and +90 degrees:
2cos(θ+30)cos(θ-30) = 1
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-> SOLUTION: Hello tutor, how do I solve the following trig function using the Factor Formula method, where theta is between -90degrees and +90 degrees:
2cos(θ+30)cos(θ-30) = 1
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Question 721787: Hello tutor, how do I solve the following trig function using the Factor Formula method, where theta is between -90degrees and +90 degrees:
You can put this solution on YOUR website! how do I solve the following trig function using the Factor Formula method, where theta is between -90degrees and +90 degrees:
2cos(θ+30)cos(θ-30) = 1
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Formula:
2cos(A)cos(B) = cos(A+B)+cos(A-B)
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Your problem:
cos[theta+30+theta-30] + cos[(theta+30)-(theta-30)] = 1
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cos[2theta] + cos(60)= 1
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cos(2theta) + (1/2) = 1
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cos(2theta) = 1/2
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2theta = 60 degrees or 2theta = -60
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theta = 30 degrees or theta = -30
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Cheers,
Stan H.
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