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ifa=cos(2pi//7)+isin(2pi//7) , then find...

if`a=cos(2pi//7)+isin(2pi//7)` , then find the quadratic equation whose roots are `alpha=a+a^2+a^4 `and `beta=a^3+a^5+a^6` .

A

`x^(2) - x + 2 = 0`

B

`x^(2) + x - 2 = 0`

C

`x^(2) - x - 2 = 0`

D

`x^(2) + x + 2 = 0`

Text Solution

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The correct Answer is:
D
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OBJECTIVE RD SHARMA ENGLISH-QUADRATIC EXPRESSIONS AND EQUATIONS -Exercise
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