Question

3.
a-1/a =3 find a^2+3a+1/a^2-3/a
plss ansr I will really mark you as brainliest
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Answer 1

Given :-

$\implies \: a - \frac{1}{a} = 3$

To Find :-

$\implies \: {a}^{2} + 3a + \frac{1}{ {a}^{2} } - \frac{3}{a}$

Solution :-

On squaring both sides, we get

$\implies \: {(a - \frac{1}{ {a} } )}^{2} = {3}^{2} \\ \\ \implies \: {a}^{2} + \frac{1}{ {a}^{2} } -2 = 9 \\ \\ \implies \: {a}^{2} - \frac{1}{ {a}^{2} } = 9 + 2 = 11$

Hence,

On putting this value in

$\implies \: {a}^{2} + 3a + \frac{1}{ {a}^{2} } - \frac{3}{a} \\ \\ \implies \: {a}^{2} + \frac{1}{ {a}^{2} } +3(a - \frac{1}{a} ) \\ \\ \implies \: 11 \: + 3(3) \\ \\ \implies \: 11 + 9 = 20$

Answer 2

Answer:

Step-by-step

a^2+1/a^2+3a-3/a

(a-1/a)^2 +2*a*1/a + 3*(a-1/a)

Putting the value of a-1/a =3

3^2 +2+3*3

9+2+9

20

The required answer is 20

Step-by-step explanation: