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:
Choice B: Only (-2, 9)
Step-by-step explanation:
Of the two choices, only the point (-2, 9) satisfies the equation:
... y = -2x +5
... 9 = -2(-2) +5 = 4 +5 = 9
Answer:
The only one that applies is g = 6 because 102 divided by 6 is 17 which is less that 33 and all the other answers are greater that 33.
Hope this helps!
Step-by-step explanation:
Answer:
The probability of the chosen ball being shiny conditional on it being red is; 0.375
Step-by-step explanation:
Let A be the event that a red ball has been chosen
Let B be the event that a shiny ball has been chosen
Let S be the total outcomes = 150 balls
Thus;
P(A ∩ B ) = 36/150
A ∩ B' = 150 - 36 - 54
A ∩ B' = 60
Thus; P(A ∩ B') = 60/150
P(A') = 54/150
P(A) = (150 - 54)/150 = 96/150
Thus, probability of the chosen ball being shiny conditional on it being red is;
P(B | A) = P(B ∩ A)/P(A)
Thus; P(B | A) = (36/150)/(96/150)
P(B | A) = 0.375