Math, asked by srijan4068, 2 months ago

If 2a - 2/a+1 = 0 , find a³-1/a³ +2​

Answers

Answered by esssahil498
0

Answer:

0

Step-by-step explanation:

2a-2/a+1=0

shift denominator to other side we get 2a-2=0

now shift -2 to other side we get 2a=2 so a=1

because 2 will get divided to the 2 at L.H.S

now but value of a which Is 1 in a³-1/a³+2

we get 1³-1/1³+2 that is 1-1/1+2 =0/3 which is 0...

hope this will help you

Answered by risusunil7gmailcom
0

Answer:

If

If

\begin{gathered}2a - \frac{2}{a} + 1 = 0...eq1 \\ \end{gathered}

2a−

a

2

+1=0...eq1

then to find the value of

\begin{gathered} {a}^{3} - \frac{1}{ {a}^{3} } + 2 \\ \\ \end{gathered}

a

3

a

3

1

+2

take cube of eq1

\begin{gathered}2a - \frac{2}{a} = - 1 \\ \\ a - \frac{1}{a} = \frac{ - 1}{2} \\ \\ {(a - \frac{1}{a}) }^{3} = {( \frac{ - 1}{2} )}^{3} \\ \\ {a}^{3} - \frac{1}{ {a}^{3} } - 3 {a}^{2} ( \frac{1}{a} ) + 3a( \frac{1}{ {a}^{2} } ) = - \frac{1}{8} \\ \\ {a}^{3} - \frac{1}{ {a}^{3} } - 3a + \frac{3}{a} = \frac{ - 1}{8} \\ \\ {a}^{3} - \frac{1}{ {a}^{3} } - 3(a - \frac{1}{a}) = \frac{ - 1}{8} \\ \\ {a}^{3} - \frac{1}{ {a}^{3} } - 3( - \frac{1}{2}) = \frac{ - 1}{8} \\ \\ {a}^{3} - \frac{1}{ {a}^{3} } + \frac{3}{2} = \frac{ - 1}{8}\end{gathered}

2a−

a

2

=−1

a−

a

1

=

2

−1

(a−

a

1

)

3

=(

2

−1

)

3

a

3

a

3

1

−3a

2

(

a

1

)+3a(

a

2

1

)=−

8

1

a

3

a

3

1

−3a+

a

3

=

8

−1

a

3

a

3

1

−3(a−

a

1

)=

8

−1

a

3

a

3

1

−3(−

2

1

)=

8

−1

a

3

a

3

1

+

2

3

=

8

−1

\begin{gathered}{a}^{3} - \frac{1}{ {a}^{3} } + 2 = \frac{ - 1}{8} - \frac{3}{2} + 2 \\ \\ = \frac{ - 1 - 12 + 16}{8} \\ \\ {a}^{3} - \frac{1}{ {a}^{3} } + 2 = \frac{3}{8} \\ \\ \end{gathered}

a

3

a

3

1

+2=

8

−1

2

3

+2

=

8

−1−12+16

a

3

a

3

1

+2=

8

3

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