Answer :
Given a 0 And
a - = 3 --------------- ( 1 )
i ) Find value of : a2 +
Squaring equation 1 , we get
( a - )2 = 32
a2 + - 2 ( a ) ( ) = 9 [ As we know ( a + b )2 = a2 + b2 + 2ab ]
a2 + - 2 = 9
a2 + = 9 + 2
a2 + = 11 ( Ans )
ii ) Find value of : a3 -
Now taking Cube of equation 1 , we get
( a - )3 = 33
a3 - - 3 ( a ) ( ) ( a - ) = 27 [ As we know ( a - b )3 = a3 - b3 - 3ab( a - b ) ]
a3 - ​- 3 ( 3 ) = 27 ( Given ​a - = 3 ​ )
a3 - - 9 = 27
a3 - = 27 + 9
a3 - = 36 ( Ans )