Cos 157.5º=-cos (180º-157.5º)=-cos 22.5=-cos(45/2)
cos Ф/2=⁺₋√((1+cosФ)/2).
In this case 157.5º is in the second quadrant, therefore we use the following equation:
cos Ф/2=-√((1+cosФ)/2). (we will have a negative number)
cos 157.5º=-cos (45/2)=-√((1+cos 45º)/2)
=-√((1+√2/2)/2)
=-√((2+√2)/4)
=-√(2+√2) / 2 (≈-0.92387...)
Answer: cos 157.5º= -√(2+√2) / 2
Answer:
6=k
Step-by-step explanation:
1/4 =2/8+3/8 =5/8
1-5/8=3/8
15. 3x - 2y = -2
3x - 3x - 2y = -3x - 2
-2y = -3x - 2
-2 -2
y = 1.5x + 1
y - y₁ = m(x - x₁)
y - 3 = ⁻²/₃(x - (-2))
y - 3 = ⁻²/₃(x + 2)
y - 3 = ²/₃(x) - ²/₃(2)
y - 3 = ⁻²/₃x - 1¹/₃
+ 3 + 3
y = ⁻²/₃x + 1²/₃
16. 230 = 0.2s + 150
- 150 - 150
80 = 0.2s
0.2 0.2
400 = s
17. y = 2x + 2
Answer:
which class question is this
