# trig

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How can I find the exact value of 4cos(7ð/4)-2sin(ð/3)?

• trig -

In a graphic calculator punch in cos(7/4) and should give you the right answer
subtract it from sin(0/3)

• trig -

the weird symbol is suppose to be pi (3.14...) not a zero. it got messed up after submitting the question

• trig -

need to show my work

• trig -

4cos(7π/4)-2sin(π/3)
= 4 cos (π/4) - 2 sin(π/3)
= 4(√2/2) - 2(√3/2)
= (4√2 - 2√3)/2

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