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find exact value of cos(23pi/6)

  • trig -

    did you notice that 23π/6 is π/6 short of 2π ?

    so and angle of 23π/6 is coterminal with -π/6
    so cos(23π/6) = cos(-π/6) = cos(π/6)

    from the 30-60-90 triangle ratios you should know that cos 30° = √3/2 ...... (30° = π/6 radians)

    then cos 23π/6 = √3/2

  • trig -

    what is the exact value of tan pi o
    ver two

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