Test 4

Question 1

If x is a positive real number, then the principal square root of x is defined as ________.

Answer 1

the positive square root of x

Question 2

In a right triangle the cosine of an acute angle is defined as the ratio of ____________.

Answer 2

the adjacent side to the hypotenuse

Question 3

In the eighteenth century, the mathematician Euler introduced the letter i to represent _____.

Answer 3

The square root of -1

Question 4

_________. is an example of a quadratic equation.

Answer 4

2x^2+4x-4=0