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If A,B,C are the three angles of a trian...

If A,B,C are the three angles of a triangle,show that:(i)cos(A+B)+cosC=0

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R G PUBLICATION-INTRODUCTION TO TRIGONOMETRY-EXERCISE
  1. If A,B,C are the three angles of a triangle,show that:(i)cos(A+B)+cosC...

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  2. IftriangleABCright-angled at B,AB=24cm,BC=7cm.Determine:(i)sinA,cosA

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  3. IntriangleABCright-angled at B,AB=24cm,BC=7cm.Determine:(ii)sinC,cosC

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  4. InFig.8.13,find tanP-cot R

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  5. If sinA=3/4,calculate cosA and tanA

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  6. Given 15 cotA=8,find sin A and sec A.

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  7. Givensectheta=13/12,calculate all other trigonometric ratios.

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  8. If angleA and angle B are acute such that cosA=cosB,then show that ang...

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  9. If cottheta=7/8evaluate:(i)((1+sintheta)(1-sintheta))/((1+costheta)(1-...

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  10. If cottheta=7/8evaluate:(ii)cot^2 theta

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  11. If 3 cotA=4,check whether(1-tan^2A)/(1+tan^2A)=Cos^2A-Sin^2A or not.

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  12. In triangle ABC,right-angled at B if tanA=1/sqrt3,find the value of:(i...

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  13. In triangle ABC,right-angled at B if tanA=1/sqrt3,find the value of:(i...

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  14. In trianglePQR,right-angled at Q,PR+QR=25cm and PQ=5cm.Determine the v...

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  15. State whether the following are true or false.Justify your answer.(i)T...

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  16. State whether the following are true or false.Justify your answer.(ii)...

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  17. State whether the following are true or false.Justify your answer.(iii...

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  18. State whether the following are true or false.Justify your answer.(iv)...

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  19. State whether the following are true or false.Justify your answer.(v)s...

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  20. Evaluate the following:(i)sin 60^@ cos30^@+sin 30^@ cos 60^@

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  21. Evaluate the following:(ii)2 tan^@ 45^@+cos^2 30^@-sin^2 60^@

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