Question

What is the exact value of cos 45° ?

Answer 1

Answer:

sqrt{2}/2

Step-by-step explanation:

Answer 2

Let the two sides of a right triangle be equal to one, which means that the hypotenuse is √2

Since cosa=adjacent side / hypotenuse

cos45=1/√2

We can rationalize the denominator by multiplying numerator and denominator by √2

√(2)/2

or if you prefer:  √(1/2)