1) Identify the statement you want to prove is true
2) Assume temporarily that the statement is false; assume the opposite is true
3) Obtain statements that logically follow from your assumption.
4) Reason logically until you reach a contradiction of a known fact.
5) Point out that your assumption must be false, and the statement must then be true.
Answer:
About 113.1
Step-by-step explanation:
Area of a circle= πr2
Radius= 6
6x6=36
36π= About 113.1
Given :
A function , x = 2cos t -3sin t .....equation 1.
A differential equation , x'' + x = 0 .....equation 2.
To Find :
Whether the given function is a solution to the given differential equation.
Solution :
First derivative of x :

Now , second derivative :

( Note : derivative of sin t is cos t and cos t is -sin t )
Putting value of x'' and x in equation 2 , we get :
=(-2cos t + 3sin t ) + ( 2cos t -3sin t )
= 0
So , x'' and x satisfy equation 2.
Therefore , x function is a solution of given differential equation .
Hence , this is the required solution .
Always, ALWAYS remeber this format: y = mx + b
In this equation, 'm' is the slope, and 'b' is the y-intercept
When you're trying to find a slope, remember that the equation is 
When finding the rise and run, look at two points that are on the graph AND on the line as well. Essentially, make sure the points you're using are integers.
In this, case, the rise is -3, and the run is 2. This means that the slope is 
Now we have the first part of our equation:
y = -
+ b
But wait! How do we find b?
Sometimes you have to input x in order to find it, but only when you're not supplied with a graph. In this case, all you have to do is look!
The point of the line that is on the y-axis is called the y-intercept.
In this graph, the y-intercept is -1
Now we have our complete equation!
y = -
- 1
Good luck!