Question

1) statement (A) : 9c3+9c4=10c4 statement (B) : ncr-1+ncr=(n+1)cr a) both a and b are true b) both a and b are false c) a is true and b is flase d) a is flase and b is true​

Answer 1

Answer:

Option A is the answer.....

Both A and B are true...

Here,⁹c3+⁹c4

n=9,r=4

As,ⁿcr+ⁿCr-1=(n+1)Cr

so,⁹c3+⁹c4=(9+1)c4=10C4

Step-by-step explanation:

Hope it helps you.....

Answer 2

Step-by-step explanation:

9c3+9c4 n=9;r=4. ncr+ncr-1=(n+1)cr. 9c3+9c4=(9+1)c4=10c4