Answer:
a.
For all non zero fraction 1(1/x), 1/x is a fraction
For all 1/(1/x), if 1/(1/x) is non zero, 1/x is a fraction
b.
For all polynomial function f(x) = x³ + x² + x - 1, the derivative (dy/dx) is a polynomial function
For all f(x) x³ + x² + x - 1, if f(x) is polynomial, f'(x) is a polynomial function
c.
For all angles x,y,z of a triangle, the sum, x + y + z = 180
For all x,y,z, if x,y and z are the angles of a triangle, x+y+z = 180
d.
For all irrational numbers x, -x is irrational
For all x, if x is irrational then -x irrational.
e.
For two integers, x and y, the sum x+y is an integer
For x,y if x and y are integers, then x + y is an integer
f.
For two fractions, x/y and a/b the product ax/by is a fraction
For x/y and a/b, if x/y and a/b are fractions then ax/by is a fraction
