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If a+1/a=3 find the valie of a^2+1/a^2​

1 Answer

4 votes

Answer:

a² + 1/a² = 7

Step-by-step explanation:

a + 1/a = 3 ; obtain the value of a² + 1/a²

Taking a + 1/a = 3

Squaring both sides ;

(a + 1/a)² = 3²

(a + 1/a)(a + 1/a) = a² + a/a + a/a + 1/a² = 3²

(a + 1/a)(a + 1/a) = a² + 1 + 1 + 1/a² = 9

a² + 2 + 1/a² = 9

a² + 1/a² = 9 - 2

a² + 1/a² = 7

Hence,

a² + 1/a² = 7

User Arthur Neves
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