Answer:
- f'(1) exists: f'(1) = -2
- f'(0) DNE
Step-by-step explanation:
<h3>a)</h3>
The function is continuous for x > 0 . The derivative is defined on that interval and is equal to ...
f'(x) = -2x . . . . . for x > 0
Then at x = 1, the derivative is ...
f'(1) = -2(1)
f'(1) = -2
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<h3>b)</h3>
The function has a jump discontinuity at x=0, so the derivative does not exist at that point. A condition for the existence of the derivative is that the function is continuous at the point of interest.
28.80 + .20X = X
.20X = X - 28.80
1/5 = .20
X/5 = X -28.80
X = 5X - 144
Set the new X equal to the original X
28.80 + .20X = 5X - 144
172.8 + .20X = 5X
172.8 = 4.8X
36 = X
36$ is the original price
To check,
28.80 + (.20 x 36) = 36
28.80 + 7.2 = 36
36 = 36
3x + 10 = 5x - 4
14 = 2x
x = 7
measure of the angles is 3(7) + 10 = 31 degrees
Let the cost of the hair dryer equal x.
The net cost plus a 40% markup equals 42, set up an equation and solve forex.
1.4x = 42
Divide both sides by 1.4
X = 42 / 1.4
X = 30
The net cost was £30
