JEE Main20254 Apr 2025Evening ShiftMathematicsBinomial TheoremActual
If (1^2 ( ¹⁵ C₁ )+2^2 ( ¹⁵ C₂ )+3^2 ( ¹⁵ C₃ )+ ) (+15^2 ( 15 15 )=2^m 3^n 5^k ), where (m, n, k N ), then ( m + n + k ) is equal to :
Options
- A19
- B21
- C18
- D20
Correct answer
A. 19
Step-by-step solution
aligned & _ r =1 ¹⁵ r ^2 ( ¹⁵ C _ r ) 15 _ r =1 ¹⁵ r ¹⁴ C _ r -1 & 15 _ r =1 ¹⁵( r -1+1) ¹⁴ C _ r -1 & 15 14 _ r =1 ¹⁵ ¹³ C _ r -2 +15 _ r =1 ¹⁵ ¹⁴ C _ r -1 & 15 14 2¹³+15 2¹⁴ & 3^1 2¹³(70+10) & 3^1 2¹³ 80 & 3^1 5^1 2¹⁷ & ~m =17 n =1 k =1 & option (1) aligned