Question: What Must Be True?

Comment on What Must Be True?

CAN YOU SHOW THIS RESULTS WITH VARIABLES ALSO, WITHOUT PUTTING VALUES . FOR EXMAPLE
IF BOTH P AND Q ARE EVEN then p( q-2) (q -1) will solve like this in sections
p* q ( even * even is even right and now this even - 2 ( which is also even) similar add /substract gives even so result is Even. This is multiplied to ( q-1 ) now
result even * q ( which is also even ) gives even , now -1 ( which is odd) from even will give odd


but if we plug values we get even as final ans
greenlight-admin's picture

We could solve it that way, but I think it will take much longer, since you still have to consider the following 4 cases:
1) p is even and q is even
2) p is even and q is odd
3) p is odd and q is even
4) p is odd and q is odd

Cheers,
Brent

q-1 and q-2 are consecutive numbers, so one of them have to be even. Since we have multiplication here, product must be Even.
greenlight-admin's picture

Perfect reasoning!

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