Question

Question number 28. Plz answer fast

Answer 1

I wish this helps you.....

Answer 2

(28)

Given x + (1/x) = 2.

On squaring both sides, we get

= > (x + 1/x)^2 = (2)^2

= > x^2 + 1/x^2 + 2 * x * 1/x = 4

= > x^2 + 1/x^2 + 2 = 4

= > x^2 + 1/x^2 = 4 - 2

= > x^2 + 1/x^2 = 2  ------ (1)

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Given Equation is (x + 1/x) = 2.

On cubing both sides, we get

= > (x + 1/x)^3 = (2)^3

= > x^3 + 1/x^3 + 3 * x * 1/x(x + 1/x) = 8

= > x^3 + 1/x^3 + 3(x + 1/x) = 8

= > x^3 + 1/x^3 + 3(2) = 8

= > x^3 + 1/x^3 + 6 = 8

= > x^3 + 1/x^3 = 2      ------------------- (2)

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On squaring equation (1) on both sides, we get

= > (x^2 + 1/x^2)^2 = (2)^2

= > x^4 + 1/x^4 + 2 * x^2 * 1/x^2 = 4

= > x^4 + 1/x^4 + 2 = 4

= > x^4 + 1/x^4 = 4 - 2

= > x^4 + 1/x^4 = 2.    --------- (3)

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Therefore, (1) = (2) = (3).

Hope it helps!