Given:
To find:
The exact value of cos 15°.
Solution:
Using half-angle identity:
Using the trigonometric identity: 
Let us first solve the fraction in the numerator.
Using fraction rule: 
Apply radical rule: ![\sqrt[n]{\frac{a}{b}}=\frac{\sqrt[n]{a}}{\sqrt[n]{b}}](https://tex.z-dn.net/?f=%5Csqrt%5Bn%5D%7B%5Cfrac%7Ba%7D%7Bb%7D%7D%3D%5Cfrac%7B%5Csqrt%5Bn%5D%7Ba%7D%7D%7B%5Csqrt%5Bn%5D%7Bb%7D%7D)
Using 
:
Answer: 15
Step-by-step explanation:
Answer:
m <1 = 30
Step-by-step explanation:
The sum of the angles of a triangle add to 180
Let x be the unknown angle
75+75+x = 180
Combine like terms
150+x =180
Subtract 150 from each side
150-150+x = 180-150
x = 30
2x^2 + 4x + 1 = 0
2x^2 + 4x + 1 - 1 = 0 - 1
2x^2 + 4x = -1
X(2x + 4) = -1
X = -1.
2x + 4 = -1
2x + 4 - 4 = -1 - 4
2x = -5
2x/2 = -5/2
X = -5/2.
I believe these are the solutions. If not you can use the quadratic formula to solve for the roots, solutions.
