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If x = 3 - 2√2 find the value of x + 1/x and x - 1/x |
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Answer» Given, x =3-2√2 We have to FIND the VALUE of x+(1/x) Taking LCM, x+(1/x) = (x²+1)/x Replacing the value of x = {(3-2√2)²+1}/3-2√2 {(3-2√2)²} can be WRITTEN as (3-2√2)(3-2√2) for our convenience = {(3-2√2)(3-2√2)+1}/3-2√2 By rationalizing, = [{(3-2√2)(3-2√2)+1}/3-2√2] × [3+2√2/3+2√2] = [(3+2√2)(3-2√2)(3-2√2) + 1(3-2√2)] / (3-2√2)(3+2√2) We know that (3-2√2)(3-2√2) = 9-8 = 1 Placing it in (3+2√2)(3-2√2) = 1(3-2√2)+1(3-2√2)/1 = 3-2√2+3-2√2 = 3+3 = 6 therefore, the value of x+(1/x) = 6 |
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