Answer:
a) 
b)

c)

d)
cos 330° = 1- 2 sin² (165°)
Step-by-step explanation:
<u><em>Step(i):-</em></u>
By using trigonometry formulas
a)
cos2∝ = 2 cos² ∝-1
cos∝ = 2 cos² ∝/2 -1
1+ cos∝ = 2 cos² ∝/2

b)
cos2∝ = 1- 2 sin² ∝
cos∝ = 1- 2 sin² ∝/2

<u><em>Step(i):-</em></u>
Given

we know that trigonometry formulas

1- cos∝ = 2 sin² ∝/2
Given

put ∝ = 315

multiply with ' 2 sin (∝/2) both numerator and denominator

Apply formulas

1- cos∝ = 2 sin² ∝/2
now we get

b)

put ∝ = 330° above formula



c )

put ∝ = 315° above formula


d)
cos∝ = 1- 2 sin² ∝/2
put ∝ = 330°

cos 330° = 1- 2 sin² (165°)
Answer:
x = 2, y= -1 Or (2, -1)
Step-by-step explanation:
Let’s solve the system using substitution. First we can set the equations equal to each other:
x-3= -2x +3
Now solve for x
3x-3= 3
3x = 6
x=2
Now that we have x, we can plug it back into one of the original equations to get y
y= x-3
y= 2-3
y = -1
Finally, the solution to the system of equations is (2, -1).
Answer:
90 degree angled lines
Step-by-step explanation:
Answer:
B C D brainlest please
Step-by-step explanation:
x y
0 6
1 7
2 8
3 9
Which statement is not always true?(1) The product of two irrational numbers is irrational.
(2) The product of two rational numbers is rational.
(3) The sum of two rational numbers is rational.
(4) The sum of a rational number and an irrational number is irrational.
The statement that is not always true is the <span>sum of two rational numbers is rational. The answer is number 3.</span>