cos4x = cos2x
We know that:
cos2x = 1-2cos^2 x
==> cos4x = 1-2cos^2 (2x)
Now substitute:
==> 1-2cos^2 (2x) = cos2x
==> 2cos^2 (2x) + cos2x - 1 = 0
Now factor:
==> (2cos2x -1)(cos2x + 1) = 0
==> 2cos2x -1 = 0 ==> cos2x =1/2 ==> 2x= pi/3
==> x1= pi/6 , 7pi/6
==> x1= pi/6 + 2npi
==> x2= 7pi/6 + 2npi
==> cos2x = -1 ==> 2x= pi ==> x3 = pi/2 + 2npi.
<span>==> x= { pi/6+2npi, 7pi/6+2npi, pi/2+2npi}</span>
Answer:
Step-by-step explanation:
The equation of a horizontal parabola in the standard form:
(h, k) - vertex
if a > 0, then open right
if a < 0, then open left
We have the vertrex (-1, -3) and the parabola is open left (a < 0).
Therefore the equation of a given parabola could be:
Answer:
0.78
Step-by-step explanation:
given that 80% of an airline's flights depart on-time and 20% do not.
Of those that depart on-time, 95% arrive on-time. Of those that depart late, 10% arrive on-time
Let A be the event that flight departs on time.
Now A and A' are mutually exclusive and exhaustive
Let B be the event the flight arrives on time
Using total probability calculation we have
the chance of someone taking a flight that will arrive on-time
= P(B)
=
Here is an example of how to do it⬇️
Set variables for the quantities we want to find.
Let x = number of apples
Let y = number of oranges
Next, we use these variables to write equations that describes the whole story.
Since the total price is $7.75 and each type of fruit has their own price, we can say
0.40x + 0.35y = 7.55
The other equation will represent the total number of fruits bought all together, as Mark mentioned. Once you have those equations, you solve the system using substitution and elimination methods to solve for the variables x and y.
(If x represents the number of peaches purchased and y represents the number of mangos purchased)
Sorry if this isn’t good explanation but I tried sorry goodluck!
