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Given costheta=-(2)/(3) and (pi)/(2)lt t...

Given `costheta=-(2)/(3) and (pi)/(2)lt theta lt pi`, find sin`2theta`.

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Since sin `2theta=2(sintheta)(costheta)`, you need to determine the value of `sintheta`. For the figrue
below, you can see that `sintheta=(sqrt(5))/(3)`. Therefore, `sin 2theta=2(sqrt(5))/(3)(-(2)/(3))=-(4)/(9)sqrt(5)`.
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ENGLISH SAT-TRIGONOMETRIC FUNCTIONS-MCQs (Exercise)
  1. Given costheta=-(2)/(3) and (pi)/(2)lt theta lt pi, find sin2theta.

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  2. Express cos320^(@) as a function of an angle between 0^(@) and 90^(@) ...

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  3. If point P(-5,12) lies on the terminal side of angletheta in standard ...

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  4. If sectheta=-(5)/(4) and sin theta gt 0, then tantheta=

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  5. If x is an angle in quadrant III and tan (x-30^(@))=cotx, find x

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  6. If 90^(@) lt alpha lt 180^(@) and 270^(@) lt beta lt 360^(@), then whi...

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  7. Expressed as a function of an acute angle, cos310^(@)=

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  8. An angle of 30 radians is equal to how many degrees?

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  9. If a sector of a circle has an arc length of 2pi inches and an area of...

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  10. If a circle has a circumference of 16 inches, the area of a sector wit...

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  11. A central angle of 40^(@) in a circle of radius 1 inch intercepts an a...

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  12. the pendulum on a clock swings through an angle 25^(@), and the tip sw...

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  13. In the figure below, part of the graph of y=sin2x is shown. What are t...

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  14. The figure below could be a portion of the graph whose equation is

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  15. As theta increases from (pi)/(4) to (5pi)/(4), the value of 4"cos"(1)/...

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  16. The function f(x)=sqrt(3)cosx+sinx has an amplitude of

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  17. For what value of P is the period off the function y=(1)/(3)cosPx equa...

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  18. If 0lexle(pi)/(2), what is the maximum value of the function f(x)="sin...

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  19. If the graph in the figure below has an equation of the form y=sin(Mx+...

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  20. If sinx=(5)/(13) and cosx=-(12)/(13), find the value of sin 2x.

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  21. If tanA=cotB and angles A and B are acute, then

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