Answer:
(4, 0)
Step-by-step explanation:
given the 2 equations
y = x - 4 → (1)
- 4x - 6y = - 16 → (2)
substitute y = x - 4 into (2)
- 4x - 6(x - 4) = - 16
- 4x - 6x + 24 = - 16
- 10x + 24 = - 16 ( subtract 24 from both sides )
- 10x = - 40 ( divide both sides by - 10 )
x = 4
substitute x = 4 into (1) for corresponding value of y
y = 4 - 4 = 0
solution is (4, 0)
True
<span>Cos(A+B)=CosACosB-SinASinB
therefore Cos(A+A)= CosACosA - SinASinA
= Cos^2A - Sin^2A</span>
Answer:
1/8
Step-by-step explanation:
sin²(π/8) − cos⁴(3π/8)
Use power reduction formulas:
1/2 (1 − cos(2×π/8)) − 1/8 (3 + 4 cos(2×3π/8) + cos(4×3π/8))
Simplify:
1/2 (1 − cos(π/4)) − 1/8 (3 + 4 cos(3π/4) + cos(3π/2))
1/2 (1 − √2/2) − 1/8 (3 + 4 (-√2/2) + 0)
1/2 − √2/4 − 1/8 (3 − 2√2)
1/2 − √2/4 − 3/8 +√2/4
1/2 − 3/8
1/8
