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If cos x.cos y + sin x.sin y = -1 then c...

If cos x.cos y + sin x.sin y = -1 then cos x + cos y is
यदि cos x.cos y + sin x.sin y = -1 हो, तो cos x + cos y का मान क्या होगा?

A

`-2`

B

1

C

0

D

2

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CHAMPION PUBLICATION-2016 TIER-II PAPER(14)-EXERCISE
  1. DeltaABC is an isosceles right angled triangle having angleC=90^(@). I...

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  2. D and E are points on the sides AB and AC respectively of DeltaABC suc...

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  3. ABCD is a trapezium in which AB||CD and AB=2CD. If its diagonals inter...

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  4. If O is the orthocentre of a triangle ABC and angleBOC=100^(@), the me...

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  5. PQ and RS are common tangents of two circles intersection at A and B. ...

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  6. If secA + tanA =a, then the value of cosA is यदि secA + tanA =a हो,...

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  7. If sin theta + cosec theta = 2, then the value of sin^7theta + cosec^7...

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  8. If cos x.cos y + sin x.sin y = -1 then cos x + cos y is यदि cos x.c...

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  9. The value of the expression 2(sin^(6)theta+cos^(6)theta)-3(sin^(4...

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  10. If cos theta=(x^2-y^2)/(x^2+y^2) then the value of cot theta is equal ...

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  11. The distance between two pillars is 120 metres. The height of one pill...

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  12. If x=cosec theta-sin theta and y = sec theta- cos theta, then the rela...

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  13. A hydrogen filled balloon ascending at the rate of 18 kmph was drifted...

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  14. The angle of elevation of an aeroplane as observed from a point 30 m a...

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  15. The angles of depression of two ships from the top of a light house ar...

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  16. The following bar diagram shows total number of males and females in f...

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  17. The following bar-diagram shows total number of males and females in f...

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  18. The following bar-diagram shows total number of males and females in f...

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  19. The following bar-diagram shows total number of males and females in f...

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  20. The following bar-diagram shows total number of males and females in f...

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