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Prove that cos48^@.cos12^@=(3+sqrt5)/8....

Prove that `cos48^@.cos12^@=(3+sqrt5)/8`.

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SRISIRI PUBLICATION-IPE:MARCH-2017(TS)-QUESTIONS
  1. Find the angle between the vectors overlinei+2overlinej+3overlinek and...

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  2. IF sin theta=4/5 and theta is not in the first quadrant, find the valu...

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  3. Prove that cos48^@.cos12^@=(3+sqrt5)/8.

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  4. IF coshx=5//2, then find the value of (i) cosh(2x) and (ii) sinh(2x)

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  5. Show that |{:(1,a,a^2),(1,b,b^2),(1,c,c^2):}|=(a-b)(b-c)(c-a)

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  6. IF overlinea,overlineb,overlinec are non-coplanar, then prove that the...

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  7. IF overlinea=2overlinei+overlinej-overlinek,overlineb=-overlinei+2over...

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  8. Find the range of 13cosx+3sqrt3 sin x-4

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  9. Solve 1+sin^2 theta=3sin thetacostheta

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  10. Show that cot(Sin^-1sqrt(13/17))=sin(Tan^-1""2/3).

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  11. In DeltaABC, if 1/(a+c)+1/(b+c)=3/(a+b+c) then show that C=60^@

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  12. If Q is the set of all rational numbers, and f:Qto Q is defined by f(x...

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  13. If f={(4,5),(5,6),(6,-4)},g={(4,-4),(6,5),(8,5)} find (iii) fg

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  14. Using Mathematical Induction, prove that statement for all n in N 1....

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  15. Solve the following system of equations by using Cramer's rule. 2x-y...

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  16. Show that the matrix A = [(1,2,1),(3,2,3),(1,1,2)] is non-singular and...

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  17. IF A=[{:(1,2,2),(2,1,2),(2,2,1):}] then show that A^2-4A-5I=O.

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  18. Find the shortest distance between the skew lines . bar(r)=(6bar(i)...

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  19. IF A+B+C=2S, then prove that cos(S-A)+cos(S-B)+cosC=-1+4cos""(S-A)/2...

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  20. Show that 1/r^2+1/r1^2+1/r2^2+1/r3^2=(a^2+b^2+c^2)/Delta^2

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