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If 0<theta<90 and tan theta= (square root 3)/2, find cos theta?

tan(t) =ã3 /2; cos(t) = 1/ã(1+(tant)^2)= 1/ã(1+3/4) = 2/ã7

right or wrong?

  • Math -

    You are doing this the hard way.

    make a diagram
    since tan theta = √3/2, and tan theta = opposite/adjacent, make the oppose √3 and the adjacent 2
    In your head you could do Pythagoras and get the hypotenuse √7
    since cos theta = adjacent/hypotenuse
    cos theta = 2/√7

    which is what you got.

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