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If alpha and beta are the root of equation x^2+x-2=0 find the value of 1/alpha^2+1/beta^2​

User TCopple
by
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2 Answers

1 vote

Answer:

Explanation:

If alpha and beta are the root of equation x^2+x-2=0 find the value of 1/alpha^2+1/beta-example-1
User Ricky Lee
by
4.3k points
5 votes

Answer:


(5)/(4)

Explanation:

Given that α and β are the roots of x² + x - 2 = 0

with a = 1, b = 1, c = - 2, then

α + β = -
(b)/(a) = - 1 and αβ =
(c)/(a) = - 2, then


(1)/(\alpha ^2) +
(1)/(\beta^2 )

=
(\beta^2+\alpha^2  )/(\alpha ^2\beta^2 )

=
((\alpha +\beta )^2-2\alpha \beta )/(\alpha ^2\beta^2 )

=
((-1)^2-2(-2))/((-2)^2)

=
(1+4)/(4)

=
(5)/(4)

User Roel Veldhuizen
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4.2k points