Option C:
x = 0
Solution:
Given equation :
To find the value of x from the given equation.
Subtract 4 from both sides of the equation.
Arrange like terms in one side of the equation.
Negative term changed to positive term when it goes to left side of the equation.
Option C is the correct answer.
The value of x is 0.
cos 2x – cosx = 0
------------ (1)
where cos2x = 2cos^2x –
1
equation (1) becomes;
<span>2cos^2x – 1 – cosx = 0 ------------ (2)</span>
Suppose cosx = y, then
equation (2) becomes;
2y^2 – 1 – y = 0
By factorization method;
(2y + 1) x (y – 1) = 0
Where 2y + 1 = 0 or y –
1 = 0
So solving both;
y = -1/2 or 1
As y = cosx
So cosx = -1/2 or 1
The above equation is true only for x = 2/3π, 0, 4/3 π
<span>The solution were find out for interval [0,2 π),
where 2 π is not included in the interval, as the interval is not a closed on
the right side.</span>
Combine like terms
-6x² + (-x²) = -6x² - x² = -7x²
-7x² + 15x + 4 is your answer
hope this helps
Answer:
Without the answers provided with the question, it would take the bus 3.85 (rounded to nearest hundredth) hours to get 30 km away from Orlando.
Step-by-step explanation:
It takes the bus approximately (when rounded to the nearest tenth) 4.3 hours to get to Orlando from Michigan hence the bus drives 70 km/h and the distance is 300 km.
You can find this by dividing 300 by 70, which equals 4.28571428571