Question

The statement "The square of any rational number is rational" can be rewritten formally as "For all rational numbers x, x 2 is rational" or as "For all x, if x is rational then x 2 is rational." Rewrite each of the following statements in the two forms "∀ x, " and "∀x, if , then " or in the two forms "∀ x and y, " and "∀x and y, if , then ."
a. The reciprocal of any nonzero fraction is a fraction.
b. The derivative of any polynomial function is a polynomial function.
c. The sum of the angles of any triangle is 180◦.
d. The negative of any irrational number is irrational.
e. The sum of any two even integers is even.
f. The product of any two fractions is a fraction.

Answer 1

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