AP EAMCET202017 Sep 2020Evening ShiftMathematicsTrigonometric Ratios & IdentitiesActual
If ( 1 2 ( ( 24 )+ ( 24 ) )= a^2+a + a ), then (a= )
Options
- A3
- B2
- C1
- D4
Correct answer
B. 2
Step-by-step solution
To get ( 24 ), we proceed as follows ( aligned 24 & = 2 ^2 24 2 24 24 & = 1+ 12 12 = 1+ ( 4 - 6 ) 1+ ( 4 - 6 ) aligned ) ( aligned & = 1+ 1 2 3 2 + 1 2 1 2 1 2 3 2 - 1 2 1 2 & =2+ 2 + 3 + 6 & and 24 =-2+ 2 - 3 + 6 & So, 1 2 ( 24 + 24 )= 2 + 6 = 2^2+2 + 2 & = a^2+a + a (given) aligned ) So, (a=2 )