NTA Abhyas JEE Main2020MathematicsDeterminantsPractice
If D r = r 15 8 r 2 35 9 r 3 25 10 , then the value of - 1 100 ∑ r = 1 5 D r - 37 5 is equal to
Options
- A5
- B2
- C9
- D3
Correct answer
D. 3
Step-by-step solution
∑ r = 1 5 D r = ∑ r = 1 5 r 15 8 ∑ r = 1 5 r 2 35 9 ∑ r = 1 5 r 3 25 10 = 15 15 8 55 35 9 225 25 10 applying C 1 ↔ C 1 - C 2 , we get, ∑ r = 1 5 D r = 0 15 8 20 35 9 200 25 10 = - 2800 0 - 1 100 ∑ r = 1 5 D r - 37 5 = 243 5 = 3