AP EAMCET · Maths · Permutation Combination
Let \(T_n\) be the number of all possible triangles formed by joining vertices of an \(n\)-sided regular polygon. If \(T_{n+1}-T_n=10\), then the value of \(n\) is
- A 5
- B 3
- C 7
- D 4
Answer & Solution
Correct Answer
(A) 5
Step-by-step Solution
Detailed explanation
A triangle can be formed from 3 vertices, so select 3 vertices out of \(x\) vertices. The number of ways of selecting 3 vertices out of \(n\) is \({ }^n C_3\).…
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