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
For the perimeter you have to consider the EXTERNAL SHAPE ONLY:
a) the perimeter of half a circle WITHOUT ITS DIAMETER is:
π.R - 2R → 3.14x1.5 - 2x1.5 → 1.71 cm
b) the perimeter of the rectangle WITHOUT THE UPPER SIDE is:
2.5+3+2.5 = 8 cm
Hence the perimeter of the figure is 1.71 + 8 = 9.71 cm
2) Area of the figure:
Area of half circle is π.R²/2 →3.14 x (1.5)²/2 → Area half circle = 3.5325 cm²
Area of rectangle = 2.5 x 3 = 7.5 cm²
Total area = 3.5325 + 7.5 = 11.0325 ≈ 11 cm²
The slope is the number in front of the x. In this equation it is 1.
The distance depends on the time.
So now we need to find the constant of variation or the constant of proportionality.
To do so we must find y(the dependent variable) and x(the independent variable).
To find the constant(k) we must find y/x
Since y/x=k
Then 2.25/.75=k
k=3
