KCET2014MathematicsProbability
If ( 21^ st ) and ( 22^ nd ) terms in the expansion of ( (1+x)⁴⁴ ) are equal, then ( x ) is equal to
Options
- A( 21 22 )
- B( 23 24 )
- C( 8 7 )
- D( 7 8 )
Correct answer
D. ( 7 8 )
Step-by-step solution
Given that ( (1+x)⁴⁴ ) [ array l Now, 44 20 x²⁰= 44 21 x²¹ x= 44 20 44 2 = (44-21) ! 21 ! (44-20) ! 20 ! = 23 ! 24 ! 21 ! 20 ! = 21 24 = 7 8 array ]