X + 1/X =7
X3 + 1/X3 =?
Answers
Answered by
1
Hope it helps! mark as brainliest
Attachments:
Answered by
1
Answer:
Hi ,
It is given that ,
x + 1/x = 7 -----( 1 )
*******************************************
We know the algebraic identity,
a³ + b³ + 3ab ( a + b ) = ( a + b )³
Or
a³ + b³ = ( a + b )³ - 3ab( a + b )
************************************
x³ + 1/x³ = (x + 1/x )³- 3 × x ×1/x(x + 1/x )
= ( x + 1/x )³ - 3( x + 1/x )
= 7³ - 3 × 7
= 7( 7² - 3 )
= 7 ( 49 - 3 )
= 7 × 46
= 322
I hope this helps you.
: )
Click to let others know, how helpful is it
Read more on Brainly.in - https://brainly.in/question/424323#readmore
Step-by-step explanation:
Similar questions