4 sin^2 θ + 13cos^2 θ = 7
sin^2 θ = 1 - cos^ θ
4 - 4cos^2 θ + 13cos^2 θ = 7
9cos^2 θ = 3
cos^2 θ = 1/3
cos θ = # (1/3) # - square root
Square root of (1/3) has +1/3 and -1/3 as values of cos
Find the key angle by doing the cos inverse of #1/3
K.A = cos^-1 #(1/3) = 0.955
θ lies in all 4 quadrants
The values of θ are:
θ = 0.955, 2.186, 4.096, 7.23
Ignore 0.955, 2.186, 4.096, 7.23 as they are out of range pi/2 = 1.571
The the value of θ = 0.955 = 0.96 (to 2 d.p) radian
Hope it helped!
Answer:
1. 19C8 = 75582
2. 19P8= 3047466240
Step-by-step explanation:
First, find the number of ways to get 8 sticks from 19. At first, you have 19 choices, then 18, then 17, all the way to 12. Giving you 19*18*17*...*13*12, or 19!/11!.
Combination:
When order doesn't matter, you have to divide 19!/11! by the number of ways to order 8 sides, or 19!/11!/8!=19C8=75582
Permutation:
When order doesn't matter, you don't have to divide 19!/11! by the number of ways to order 8 sides, since you count each of these, and 19!/11!=19P8=3047466240.
We will use the equation 74.06-56.48=? To find the change in prices, aka how much more money was spent. That equals 17.58. So A, Michael spent $17.58 more than Denise.
Answer:
f(x) = -4x + 80
Step-by-step explanation:
You are given two points,
(5, 60) and (10, 40)
in order to get the equation, let's use the form slope-intercept form
m = (y1 - y2) / (x1 - x2)
m = (60 - 40) / (5 - 10)
m = 20/-5
m = -4
Get the x intercept
y = mx + b
60 = (-4)(5) + b
b = 60+20
b = 80
so the equation is
y = -4x + 80
f(x) = -4x + 80
