Prove abN a b not equal to 0 Hint Prove the statement by ind
Prove a,bN a· b not equal to 0.
Hint: Prove the statement by induction with respect to b.
PLZ help me...thank you so much!
Solution
a,b belongs to N.
This implies a and b must be +ve numbers.
The product of two +ve natural number can never be zero. So, a.b not equal to zero.
a x b = ab (+ve number). -----(1)
Mathematical induction:
Let a=1 and b=2, then a x b= 1 x 2= 2 (not equal to 0).
To prove its true for b+1 also:
a (b+1) = ab + a
Now, ab is +ve from equation (1). and a belongs to N(+ve). So, the sum of two positive natural numbers is +ve.
Hence proved, a(b+1) is not equal to zero.
