CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

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
loader
B
10
loader
C
8
loader
D
7
loader

Solution

The correct option is A 5
we know that a triangle needs $$3$$ vertices to be formed so out of $$n$$ vertices $$3$$ should be chosen$$=\ ^nC_3$$

According to the given condition, we can write that

$$^{n+1}C_{3}-^{n}C_{3}=10$$

$$\Rightarrow ^{n}C_{2}=10$$

$$\Rightarrow n=5$$

Maths

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image