If x, y, z are integers, is x(y^2 + z^3) even?
1] x is odd.
2] The product xyz is odd.
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Question stem: if x(y^2 + z^3) is evenvscid wrote:If x, y, z are integers, is x(y^2 + z^3) even?
1] x is odd.
2] The product xyz is odd.
either x is even and y can be either even or odd or z could be either even or odd, or all x y & z are odd.
Statement I
x is odd, we dont know anything y or z
if x is odd, y and z are also odd, then entire expression is even, because odd+odd = even
if y is even and z is odd or vice versa, then odd+even = odd, the entire expression becomes odd.
Insufficient.
Statement II
xyz = odd
this means x is odd, y is odd & z is odd
odd ( odd+odd) = odd* even = even, since odd+odd = even
Sufficient.
Hence, B.
No rest for the Wicked....