Answer:
The most straightforward way to obtain the expression for cos(2x) is by using the "cosine of the sum" formula: cos(x + y) = cosx*cosy - sinx*siny. cos(2x) = cos² (x) - (1 - cos²(x)) = 2cos²(x) - 1. = 2cos²(x) - 1.
Step-by-step explanation:
Answer:
y=2x+10
Step-by-step explanation:
In line equations its helpful to write your line in the form y = ax + b. This helps because a is always the gadient of the line and b is always the y intercept.
In this case it is y=2x+3
All parallel lines have the same gradient. The gradient of this line = 2.
If the line crosses the x axis at x=-5, then when x =-5 y = 0.
If you put all this in the form y =ax + b you get 0 = 2(-5) +b
So all you need to do to find b is rearrange. b = 10.
Therefore your line has gradient 2 and y intercept 10.
y = 2x + 10
Answer:
C
Step-by-step explanation:
From the given coordinates
A(6, 0), B(0, 0) then AB = 6 - 0 = 6
B(0, 0), C(0, 8) then BC = 8 - 0 = 8
To calculate AC use Pythagoras' theorem on the right triangle formed
AC² = AB² + BC² = 6² + 8² = 36 + 64 = 100
Take the square root of both sides, hence
AC = 
= 10
Perimeter = AB + BC + AC = 6 + 8 + 10 = 24 → C
Answer:
0.125 or 1/8
Step-by-step explanation:
2^3 +2^-3= (2*2*2) + (1/(2*2*2))= 8 + 1/8= 8 + 0.125= 8.125
4^3 +1= (4*4*4) + 1= 64 + 1= 65
8.125/65= 0.125 or 1/8
