Question
Which of the following is an equation of the line tangent to the graph of y=cosx at \(x=\frac{\pi }{2}\)?
A \(y=x+\frac{\pi }{2}\)
B\( y=x-\frac{\pi }{2}\)
C \(y=-x+\frac{\pi }{2}\)
D \(y=-x-\frac{\pi }{2}\)
Answer/Explanation
Ans: C
Question
At time t=0, a storage tank is empty and begins filling with water. For t>0 hours, the depth of the water in the tank is increasing at a rate of W(t) feet per hour. Which of the following is the best interpretation of the statement W′(2)>3 ?
A Two hours after the tank begins filling with water, the depth of the water is increasing at a rate greater than 3 feet per hour.
B Over the first two hours after the tank begins filling with water, the depth of the water is always increasing at a rate greater than 3 feet per hour.
C Two hours after the tank begins filling with water, the rate at which the depth of the water is rising is increasing at a rate greater than 3 feet per hour per hour.
D Over the first two hours after the tank begins filling with water, the rate at which the depth of the water is rising is always increasing at a rate greater than 3 feet per hour per hour.
Answer/Explanation
Ans:C
In the expression , the 2 represents the value of the independent variable and is therefore the number of hours since the tank began filling with water. , being the value of a derivative, is the rate of change of , that is, the rate of change of the rate at which the depth of the water is rising; in this case, 2 hours after the tank begins filling with water. The units for the derivative would be the units of W per unit of time; thus, feet per hour per hour. The statement says that at time 2 hours after the tank begins filling with water, the rate at which the depth of the water is rising, , is increasing at a rate that is greater than 3 feet per hour per hour.
Question
When x=2e, is
A \(\frac{1}{2e}\)
B 1
C ln(2e)
D nonexistent
Answer/Explanation
Ans:A
Question
Let f be the function defined by \(f(x)=\ln (x^{2}+1)\) and let g be the function defined by \(g(x)=x^{5}+x^{2}\).The line tangent to the graph of f at x = 2 is parallel to the line tangent to the graph of g at x = a, where a is a positive constant. What is the value of a ?
A 0.246
B 0.430
C 0.447
D 0.790
Answer/Explanation
Ans:C
Question
An equation of the line tangent to the graph of \(f(x)=x(1-2x)^{3}\) at the point (1,−1) is ,
A y=−7x+6
B y=−6x+5
C y=−2x
D y=2x−3
E y=7x−8
Answer/Explanation
Ans:E
Question
Shown above is the graph of the differentiable function f along with the line tangent to the graph of f at x=3. What is the value of f′(3)?
A \(-\frac{1}{2}\)
B -2
C 4
D \(\frac{11}{2}\)
Answer/Explanation
Ans:A
The derivative of f at x=3 is the slope of the line tangent to the graph of f at x=3. The slope of the line is \(\frac{\Delta y}{\Delta x}=\frac{4-3}{3-5}=-\frac{1}{2}\).
Question
Let be a differentiable function with f(1)=−2. The graph of f′, the derivative of f, is shown above. Which of the following statements is true about the line tangent to the graph of at x=1?
A The tangent line has slope and passes through the point (1,−2).
B The tangent line has slope −1 and passes through the point (1,−1).
C The tangent line has slope 0 and passes through the point (1,−2).
D The tangent line has slope 0 and passes through the point (1,−1)
Answer/Explanation
.Ans:A
The slope of the line tangent to the graph of f at x=1is given by f′(1). From the graph, f′(1)=−1. Because f(1)=−2, the tangent line passes through the point (1,−2).
Question
Shown above is the graph of the differentiable function , along with the line tangent to the graph of at x=2. What is the value of f′(2) ?
A \(\frac{1}{2}\)
B 2
C 3
D 4
Answer/Explanation
Ans:A
The derivative of at x=2 is the slope of the line tangent to the graph of fat x=2. The slope of the line is \(\frac{\Delta y}{\Delta x}=\frac{4-3}{4-2}=\frac{1}{2}\).
Question
The graph of a function with f(b)>f(a) is shown above for a≤x≤b. The derivative of f exists for all x in the interval except x=0.For how many values of , for a<c<b does ?
A Zero
B One
C Two
D Three
Answer/Explanation
Ans:D
The expression \(\frac{f(b)-f(a)}{b-a}\) is the average rate of change of over the interval a≤x≤b and is equal to the slope of the secant line passing through the points (a,f(a)) and (b,f(b)). The expression is the instantaneous rate of change of at x=c and is equal to the slope of the line tangent to the graph of f at x=. There are four points on the graph of at which the slope of the tangent line is equal to the slope of the secant line. Two of the points occur to the left of the -axis, and two of the points occur to the right of the -axis.
Question
The graph of a function f with f(b)>f(a) is shown above for a≤x≤b. The derivative of f exists for all in the interval a<x<b except x=0.For how many values of c, for a<c<b, does ?
A Zero
B Two
C Three
D Four
Answer/Explanation
Ans:D
The expression \(\frac{f(b)-f(a)}{b-a}\) is the average rate of change of f on the interval a≤x≤b and is equal to the slope of the secant line passing through the points (a,f(a)) and (b,f(b)). The expression is the instantaneous rate of change of at x=c and is equal to the slope of the line tangent to the graph of at x=c. There are four points on the graph of at which the slope of the tangent line is equal to the slope of the secant line. Two of the points occur slightly to the left of the interior local maxima. Two of the points occur slightly to the right of the local minima with horizontal tangents.
Question
Let f be the function defined above. Which of the following statements is true?
A f is not differentiable at x=5 because is not continuous at x=5.
B f is not differentiable at x=5 because the graph of f has a sharp corner at x=5.
C f is not differentiable at x=5 because the graph of f has a vertical tangent at x=5.
D f is not differentiable at x=5 because f is not defined at x=5.
Answer/Explanation
Ans:D
The limits and
are not equal. Therefore, is not continuous at x=5, and the graph of f would not have a sharp corner at x=5.
are not equal. Therefore, is not continuous at x=5, and the graph of would not have a sharp corner at x=5.
Question
The figure above shows the graph of a function , which has a vertical tangent at x=4 and a horizontal tangent at x=5. Which of the following statements is false?
A f is not differentiable at x= because the graph of f has a jump discontinuity at x=2.
B is not differentiable at x=4 because the graph of has a vertical tangent at x=4.
C is not differentiable at x= because the graph of f has a horizontal tangent at x=.
D is not differentiable at x= because the graph of has a removable discontinuity at x=7.
Answer/Explanation
Ans:C
A function is differentiable at points at which the line tangent to the graph is horizontal.
Question
The graph of the function f shown in the figure above has a vertical tangent at the point (2,0) and horizontal tangents at the points (1, -1) and (3,1) . For what values of x, -2<x<4, is f not differentiable?
A 0 only
B 0 and 2 only
C 1 and 3 only
D 0,1 and 3 only
E 0,1,2 and 3
Answer/Explanation
Ans:B
Question
The graph of a function f is shown above. At which value of x is f continuous, but not differentiable?
A a
B b
C c
D d
E e
Answer/Explanation
Ans:a
Question
A I only
B II only
C III only
D I and II only
E I,II and III
Answer/Explanation
Ans:A
Question
Let f be the function given by \(f(x)=(2x-1)^{5}(x+1)\) .Which of the following is an equation for the line tangent to the graph of f at the point where x=1?
A y=21x+2
B y=21x−19
C y=11x−9
D y=10x+2
E y=10x−8
Answer/Explanation
Ans:B
Question
If \( f(x)=2+|x-3|\)for all x, then the value of the derivative f ′(x ) at x = 3 is.
(A) -1 (B) 0 (C) 1 (D) 2 (E) nonexistent
Answer/Explanation
Ans:E
Question
If \(y=tan u\) ,u=\(v-\frac{1}{v}\), and v= ln x, what is the value of x, what is the value of \(\frac{dy}{dx}at x=e\)?
(A)0 (B)\(\frac{1}{e}\) (C)1 (D)\(\frac{2}{e} \) (E)\(sec^{2}e\)
Answer/Explanation
Ans:D
Question
The slope of the line tangent to the graph of \(y=In(x^{2})\) at \(x=e^{2}\) is
(A)\(\frac{1}{e^{2}}\) (B)\(\frac{2}{e^{2}}\) (C)\(\frac{4}{e^{2}}\) (D)\(\frac{1}{e^{4}}\) (E)\(\frac{4}{e^{4}}\)
Question
The slope of the line tangent to the graph of \(y=In(x^{2})\) at \(x=e^{2}\) is
(A)\(\frac{1}{e^{2}}\) (B)\(\frac{2}{e^{2}}\) (C)\(\frac{4}{e^{2}}\) (D)\(\frac{1}{e^{4}}\) (E)\(\frac{4}{e^{4}}\)
Answer/Explanation
Ans:A
Question
let \(f(x)=\left | sinx -\frac{1}{2} \right |\).
(A)\( \frac{1}{2}\) (B) 1 (C) \(\frac{3}{2}\) (D)\(\frac{\pi }{2} \) (E) \(\frac{3\pi }{2}\)
Answer/Explanation
Ans:A
Question
\(\frac{dy}{dx}=4y\) and if y=4 when x=0 then y=
(A)\(4e^{4x}\) (B)\(e^{4x} \) (C)\(3+e^{4x}\) (D)\(4+e^{4x}\) (E) \(2x^{2x}+4\)
Answer/Explanation
Ans:E
Question
If \(f(x)=x, then f'(5)\)=
(A) 0 (B) \(\frac{1}{5}\) (C) 1 (D) 5 (E) 25
Answer/Explanation
Ans:C
Question
The slope of the line tangent to the graph of \(y=In\left ( \frac{x}{2} \right ) \)at x=4 is
(A) \(\frac{1}{8}\) (B)\(\frac{1}{4}\) (C)\(\frac{1}{2}\) (D) 1 (E) 4
Answer/Explanation
Ans:B
Question
\(\frac{d}{dx}\left ( \frac{1}{x^{3}}-\frac{1}{x}+x^{2} \right )\) at x= -1 is
(A) −6 (B) -4 (C) 0 (D) 2 (E) 6
Answer/Explanation
Ans:B
Question
An equation of the line tangent to the graph of \(f ( x)= x(1 − 2x)^{3}\) at the point (1,-1 ) is
(A) y =−7 x+6 (B) y=-6x+5 (C) y=-2x+1 (D)y=2x-3 (E)y=7x-8
Answer/Explanation
Ans:A
Question
(A) \(-\frac{1}{2}\) (B) \(\frac{1}{2} \) (C)\(\frac{\sqrt{2}}{2}\) (D)\(\frac{\sqrt{3}}{2}\) (E)\(\sqrt{3}\)
Answer/Explanation
Ans:B
Question
If \(f(x)=\sqrt{2x}\), then \(f'(2)=\)
(A)\( \frac{1}{4}\) (B)\(\frac{1}{2}\) (C)\(\frac{\sqrt{2}}{2}\) (D) 1 (E) \(\sqrt{2}\)
Answer/Explanation
Ans:B
Question
If \(f(x)=(x^{2}-2x-1)^{\frac{2}{3}}\), then f'(0)is
(A)\(\frac{4}{3}\) (B)0 (C)\(-\frac{2}{3}\) (D)\(-\frac{4}{3}\) (E)-2
Answer/Explanation
Ans:A
Question
If f is a differentiable function, then f ′( a) is given by which of the following?
I.\(\lim_{h\rightarrow 0}\frac{f(a+h)-f(a)}{h}\)
II.\(\lim_{h\rightarrow a}\frac{f(a+h)-f(x-a)}{h}\)
III.\(\lim_{h\rightarrow a}\frac{f(a+h)-f(x-a)}{h}\)
(A) I only (B) II only (C) I and II only (D) I and III only (E) I, II, and III
Answer/Explanation
Ans:C