Write the expression 
in the simplest form.
nCr+1 + nCr-1 + 2 
nCr
= (nCr+1 + nCr) + (nCr + nCr-1)
⇒ (nCr + nCr-1 = n+1Cr)
= n+1Cr+1 + n+1Cr
⇒ (nCr + nCr-1 = n+1Cr)
= n+2Cr+1
1
Write the expression in the simplest form.
nCr+1 + nCr-1 + 2 nCr
= (nCr+1 + nCr) + (nCr + nCr-1)
⇒ (nCr + nCr-1 = n+1Cr)
= n+1Cr+1 + n+1Cr
⇒ (nCr + nCr-1 = n+1Cr)
= n+2Cr+1