Answer:
(3, -3) is correct
Step-by-step explanation:
-4 × 3 = -12. -12 + 9 = -3
4 (e)
sin^8 x - cos^8 x
= (sin^4 x + cos^4 x)(sin^4 x - cos^4 x)
= (sin^4 x + cos^4 x)(sin^2 x - cos^2x)(sin^2 x +cos^2 x)
= (sin^4x + cos^4 x)( sin^2 x- cos^2 x)
Sorry I cant do 4 (d).
Answer: cos(Θ) = (√15) / 4
Explanation:
The question states:
1) sin(Θ) = 1/4
2) 0 < Θ < π / 2
3) find cos(Θ)
This is how you solve it.
1) Use the fundamental identity (in this part I use α instead of Θ, just for facility of wirting the symbols, but they mean the same for the case).

2) From which you can find:

3) Replace sin(α) with 1/4
=>

=>

4) Given that the angle is in the first quadrant, you know that cosine is positive and the final answer is:
cos(Θ) =

.
And that is the answer.
(x^3 - y^3)(x^3 + y^3)
You can get this by factoring based on the a^2 - b^2 model
Step-by-step explanation:
(3x+6)= 48(Alternate angles)
3x=48-6
3x=42
x=14
2y+48=5y-9 (Sum of two opposite interior angles= exterior angle)
48+9=5y-2y
57=3y
y=19