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If a2 + 1/a2 = 11, find the value of a3 - 1/a3 |
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Answer» given a^2+1/a^2=11 (a+1/a)^2=13 (a+1/a)=SQRT13 (a-1/a)^2=(a+1/a)^2-4 =13-4=9 (a-1/a)=+or-3 we KNOW that a^3-b^3=(a-b)(a^2+ab+b^2) a^3-1/a^3=(a-1/a)(a^2+1+1/a^2) =3(12) =36
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