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: 28 ft
Step-by-step explanation:
Multiply 3,4, and 7 to get 84 ft cubed. To find the volume of a pyramid, divide by 3 to get 28 ft.
Answer:
mFG = 67r ( Where r is the radius of the circle)
∠ECF = 67°
Step-by-step explanation:
i) m FG
Join CG
∠GCF=67°
(As FG=ED and equal chords subtend equal angle at center)
Now The length of the minor arc is given by the formula
m arc FG =

∠C=67
m arc FG = 
m arc FG = 67r
Where r is the radius of the circle.
2. ∠ECF = 67°
It is because of the rule which says that equal chords subtend equal angle at center
DE = EF
Hence ∠DCE = ∠ECF
Answer:
6. Find the product for both sets of polynomials below by multiplying vertically. (4 points: 2 points for each product)
A)
4x^4 - 4x^3 - 16x^2 + 16x
B)
4x^4 - 4x^3 - 16x^2 + 16x
7. Are the two products the same when you multiply them vertically? (1 point)
Yes, the two products are the same when you multiply them.
Making a Decision:
8. Who was right, Emily or Zach? Are the products the same with the three different methods of multiplication? (1 point)
Emily was right, the products are the same with all three different methods of multiplication.
9. Which of these three methods is your preferred method for multiplying polynomials? Why? (1 point)
I prefer the table method because it is easier to understand what is going on, know where and what to do, and it is nicely and neatly laid out in front of me.