In spoken language, we are often careless in our use of words.
The numbers at which <em>f</em> is not differentiable are;<u> -1, and 2</u>
The reason the above list of numbers at which <em>f</em> is not differentiable are correct are given as follows:
<em>Question; Please find attached a graph that can be used to solve the question</em>
- A function is not differentiable at a point where the function has a discontinuity. That is a point on the graph were there is a break in the graph
Therefore, the given graph of <em>f</em> shows that <u>the function is not differentiable at x = -1</u>, the point where the graph has a discontinuity
- A function is not differentiable at a point where the graph of the function has a kink or corner.
The graph of <em>f</em> has a kink at x = 2, therefore, <u>the function is also not differentiable at x = 2</u>
Learn more about differentiability of a function here:
brainly.com/question/18187058
The angle of elevation of the ground is the angle between the ground and the line of sight
The angle of elevation of the ground is 30.46 degrees
<h3>How to calculate the angle of elevation</h3>
The angle of elevation is calculated using the following tangent ratio

Evaluate the quotient

Take the arc tan of both sides

Using a calculator, we have:
= 30.46
Hence, the angle of elevation of the ground to the nearest tenth of a degree is 30.46 degrees
Read more about elevation and distance at:
brainly.com/question/7243416
The percentage increase of the change in price is gotten as; 48%
<h3>How to calculate percentage price increase?</h3>
We are given;
Old Cost Price = $20
New Cost Price = $9.60
Thus, the increase in price is;
29.60 - 20 = $9.60
The percentage increase is;
Percent increase = (29.60 - 20)/20 * 100%
Percentage Increase = 9.60/20 * 100%
Percentage Increase = 0.48 * 100% = 48%
Complete Question is;
The last time i bought this product , it cost $20.00 but it looks like it cost 29. 60 today? What is the percentage increase?
Read more about Percentage Price Increase at; brainly.com/question/1476828
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