Advertisements
Advertisements
प्रश्न
Verify that 8C4 + 8C3 = 9C4.
उत्तर
LHS = 8C4 + 8C3
`= (8*7*6*5)/(4*3*2*1) + (8*7*6)/(3*2*1)`
= 7 × 2 × 5 + 8 × 7
= 70 + 56
= 126
RHS = 9C4
`= (9 xx 8 xx 7 xx 6)/(4 xx 3 xx 2 xx 1)`
= 9 × 7 × 2
= 126
∴ LHS = RHS
Hence verified.
APPEARS IN
संबंधित प्रश्न
If nPr = 1680 and nCr = 70, find n and r.
A committee of 5 is to be formed out of 6 gents and 4 ladies. In how many ways this can be done when
- atleast two ladies are included.
- atmost two ladies are included.
How many code symbols can be formed using 5 out of 6 letters A, B, C, D, E, F so that the letters
- cannot be repeated
- can be repeated
- cannot be repeated but must begin with E
- cannot be repeated but end with CAB.
The value of n, when np2 = 20 is:
The number of ways selecting 4 players out of 5 is
Prove that `""^35"C"_5 + sum_("r" = 0)^4 ""^((39 - "r"))"C"_4` = 40C5
Find the total number of subsets of a set with
[Hint: nC0 + nC1 + nC2 + ... + nCn = 2n] 4 elements
How many triangles can be formed by joining 15 points on the plane, in which no line joining any three points?
Choose the correct alternative:
The number of parallelograms that can be formed from a set of four parallel lines intersecting another set of three parallel lines
Choose the correct alternative:
If 10 lines are drawn in a plane such that no two of them are parallel and no three are concurrent, then the total number of points of intersection are
