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If n is an integer then show that (1 ...

If n is an integer then show that
`(1 + cos theta + i sin theta)^(n) + (1 + cos theta - i sin theta )^(n) = 2^(n+1) cos ^(n) ( theta//2) cos ((n theta)/2)`.

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AAKASH SERIES-DEMOIVRE'S THEOREM-EXERCISE - 6 (LONG ANSWER QUESTIONS)
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  2. If n is a positive integer, show that ( P + iQ)^(1//n) + ( P - iQ)^...

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  3. If n is an integer then show that (1 + cos theta + i sin theta)^(n...

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  4. If alpha, beta are the roots of the equation x^(2) - 2x + 4 = 0 the...

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  5. If cos alpha+cos beta+cos gamma=0 & sin alpha +sin beta +sin gamma=0. ...

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  6. If cos alpha+cos beta+cos gamma=0 & sin alpha +sin beta +sin gamma=0. ...

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  7. If cos alpha + cos beta + cos gamma = 0 = sin alpha + sin beta + ...

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  8. If cos alpha + cos beta + cos gamma = 0 = sin alpha + sin beta + ...

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  9. If cos alpha + cos beta + cos gamma = 0 = sin alpha + sin beta + ...

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  10. If cos alpha + cos beta + cos gamma = 0 sin alpha + sin beta + sin g...

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  11. Solve the following equations. x^(4) - 1 = 0

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  12. Solve the following equations. x^(5) + 1 = 0

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  13. Solve the following equations. x^(4) + 1 = 0

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  14. Solve the following equations x^(11)-x^7+x^4-1=0

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  15. If ( 1 + x ) ^(n) = a(0) + a (1) x + a(2) x^(2) + ………. + a(n)x^(n...

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  16. If ( 1 + x ) ^(n) = a(0) + a (1) x + a(2) x^(2) + ………. + a(n)x^(n...

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  17. The common roots of the equation x^(12)-1=0,x^4+x^2+1=0 are

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  18. Find the number of 15^(th)roots of unity, which are also 25^(th) roots...

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  19. If z^(2) + z + 1 = 0, where z is a complex number , prove that ( z...

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  20. If 1,alpha,alpha^2,alpha^3,…,alpha^(n-1) be the n^(th) roots of unity,...

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