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If A,B,C are angles in a triangle , then prove that `cosA+cosB+cosC=1+4sin. (A)/(2)sin. (B)/(2) sin. (C)/(2)`

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SRISIRI PUBLICATION-IPE:MARCH-2018(AP)-QUESTIONS
  1. IF the vectors -3overlinei+4overlinej+lamdaoverlinek,muoverlinei+8over...

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  2. Find the vector equation of plane passing through Points (0,0,0) , (0,...

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  3. Find the angle between the vectors overlinei+2overlinej+3overlinek and...

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  4. Find sin330^@.cos120^@+ cos210^@.sin300^@

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  5. Find the extreme values of cos 2x+cos^2x

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  6. Prove that cosh2x=2cosh^(2)x-1

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  7. IF A=[{:(7,-2),(-1,2),(5,3):}].B=[{:(-2,-1),(4,2),(-1,0):}] then find ...

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  8. Show that the four points -overlinea+4overlineb-3overlinec,3overlinea+...

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  9. Let overlinea and overlineb be vectors, satisfying |overlinea|=|overli...

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  10. If A is not an integral multiple of (pi)/(2), prove that (i) tan A +...

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  11. Solve sqrt3sintheta-costheta=sqrt2

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  12. Prove that Sin^-1""4/5+Sin^-1""5/13+Sin^-1(16/65)=pi/2

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  13. If a = (b-c) "sec" theta, then prove that tan theta = (2sqrt(bc))/(b-c...

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  14. If f: A to B, g:B to C are two bijective functions then prove that gof...

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  15. Using the P.M.I 2prove that 1/1.3+1/3.5+1/5.7+....+n terms=n/(2n+1)

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  16. Show that |{:(a+b+2c,a,b),(c,b+c+2a,b),(c,a,c+a+2b):}|=2(a+b+c)^3

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  17. Solve the system of equations 2x-y+3z=9,x+y+z=6,x-y+z=2 using Gauss J...

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  18. Fo any four vectors overlinea,overlineb,overlinec and overlined, prove...

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  19. If A,B,C are angles in a triangle , then prove that cosA+cosB+cosC=1+4...

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  20. Show that r+r(3)+r(1)-r(2)=4RcosB.

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