SOLUTION: prove that ncr+2[ncr-1]+ncr+2=n+2cr+2

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Question 1129788: prove that ncr+2[ncr-1]+ncr+2=n+2cr+2
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Thanks but no thanks for not using parentheses so we have to try to figure out what the problem says....

The most likely meaning I can see for the statement we are to prove is

C(n,r)+2C(n,r-1)+C(n,r+2) = C(n+2,r+2)

In that case, it can't be proved, because it is not true. Almost any (or perhaps any) choices for n and r will show the statement to be false.