Most Important Selected Qs for JEE AdvancedMathematicsBasics of Mathematics
Which of the following is equal to integer?
Options
- A7^ - ₇ 6 +81^ (1- ₉ 2 )
- B₆ 3 ₆ 12+ ( ₆ 2 )^2
- C1 ₅ 3 + 1 ₆ 3 - 1 ₁₀ 3
- D( [3] 2 + [3] 5 )( [3] 4 - [3] 10 + [3] 25 )
Correct answer
D. ( [3] 2 + [3] 5 )( [3] 4 - [3] 10 + [3] 25 )
Step-by-step solution
(1) 7^ - ₇ 6 +81^ (1- ₉ 2 ) =7^ - ₇ 6 +81 81^ - ₉ 2 = 1 6 + 81 4 (2) (1- ₆ 2 ) (1+ ₆ 2 )+ ( ₆ 2 )^2=1- ( ₆ 2 )^2+ ( ₆ 2 )^2=1 (3) ₃ 5+ ₃ 6- ₃ 10= ₃ 3=1 (4) (2^ 1 3 +5^ 1 3 ) (2^ 2 3 -2^ 1 3 5^ 1 3 +5^ 2 3 )=2+5=7