D x= -9
Y=9
Because 4(-9)+45=9
I just put in each one and d got it right.
Answer:
x = {nπ -π/4, (4nπ -π)/16}
Step-by-step explanation:
It can be helpful to make use of the identities for angle sums and differences to rewrite the sum:
cos(3x) +sin(5x) = cos(4x -x) +sin(4x +x)
= cos(4x)cos(x) +sin(4x)sin(x) +sin(4x)cos(x) +cos(4x)sin(x)
= sin(x)(sin(4x) +cos(4x)) +cos(x)(sin(4x) +cos(4x))
= (sin(x) +cos(x))·(sin(4x) +cos(4x))
Each of the sums in this product is of the same form, so each can be simplified using the identity ...
sin(x) +cos(x) = √2·sin(x +π/4)
Then the given equation can be rewritten as ...
cos(3x) +sin(5x) = 0
2·sin(x +π/4)·sin(4x +π/4) = 0
Of course sin(x) = 0 for x = n·π, so these factors are zero when ...
sin(x +π/4) = 0 ⇒ x = nπ -π/4
sin(4x +π/4) = 0 ⇒ x = (nπ -π/4)/4 = (4nπ -π)/16
The solutions are ...
x ∈ {(n-1)π/4, (4n-1)π/16} . . . . . for any integer n
Answer:
x = 9
Step-by-step explanation:
The sum of the 4 angles in a quadrilateral = 360°
Sum the given angles and equate to 360
90 + 109 + 9x - 5 + 85 = 360, that is
9x + 279 = 360 ( subtract 279 from both sides )
9x = 81 ( divide both sides by 9 )
x = 9
Answer:
Step-by-step explanation:
Given is the hexagonal pyramid.
We know the radius of the base is same as its side.
<u>Find the base area:</u>
- A = 3√3/2a²
- A = 3√3/2*6² = 54√3
<u>Given the height and radius, find the side of the lateral triangular faces:</u>
Each of 6 triangles have sides 10, 10 and 6 units.
<u>Find the area using heron's formula:</u>
- s = P/2 = (10*2 + 6)/2 = 13
- s - a = s - b = 13 - 10 = 3
- s - c = 13 - 6 = 7
<u>Total surface area:</u>
Correct choice is B
I don't know the answer, but I suggest downloading the app: PhotoMath. It scans a math problem and shows you how to complete the problem. I hope this helped~!
