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(a)Derive geometrically that cos(x+y)=co...

(a)Derive geometrically that `cos(x+y)=cos x cos y-sin x sin y`.Hence deduce the valueof `cos 75^@`

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OSWAAL PUBLICATION-SOLVED PAPER 2020-2-EXERCISE
  1. Consider the experiment of rolling die. Let A be the event 'getting a ...

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  2. Consider the experiment of rolling die. Let A be the event 'getting a ...

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  3. A committee of two persons is selected from two men and two women.What...

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  4. A committee of two persons is selected from two men and two women. Wha...

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  5. Define a modulus function.If the function f:R rarr R is defined by f(x...

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  6. Prove that : (sin 5x-2sin3x+sinx)/(cos5x-cosx)=tanx

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  7. 1^(2)+2^(2)+3^(2)+..........+n^(2)=(n(n+1)(2n+1))/(6)

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  8. Solve the inequalities graphically 3x+4yle60,x+3yle30,xge0,yge0.

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  9. What is the number of ways of choosing 4 cards from a pack of 52 play...

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  10. What is the number of ways of choosing 4 cards from a pack of 52 play...

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  11. What is the number of ways of choosing 4 cards from a pack of 52 play...

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  12. What is the number of ways of choosing 4 cards from a pack of 52 play...

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  13. State and prove Bionomial theorem for any positive integer n.

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  14. Derive the equation of a straight line having the intercepts 'a' & 'b'...

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  15. Find the co-ordinates of the point P which divides the line segment jo...

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  16. Prove that underset (x rarr 0) lim (sin x)/x=1,where x is in radian an...

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  17. (a)Derive geometrically that cos(x+y)=cos x cos y-sin x sin y.Hence de...

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  18. Find the sum to n terms of the series , 5+11+19+29+41…

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  19. Derive the equation of the ellipse in the form (x^(2))/(a^(2))+(y^(2))...

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  20. Find the derivative of (x + cos x)/(tan x) with respect to x

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