Implicit Differentiation
Inverse Differentiation
Free Points!
Optimization
Linear Approximation
100

Let the function y(x) be defined implicitly on 0<x<0 by ln(x/e^y)=cos(y). 

What is the derivative of this function? 

By using the chain rule and applying the inverses of both the natural logarithm and of cosine, the resulting derivative should be: 

y'=1/(x-sin(y)x) 

100

Let f(x)=sin(x^4) 

Is the function increasing or decreasing at x=10? 

f'(x)=4x^3(cos(x^4))

=4(10)^3(cos(10)^4)

=-3808.62 

The derivative at x=10 is negative, therefore the function should be decreasing. 

100

Why do people appear bright until they speak? 

Because light travels faster than sound

100

Let f be a differentiable function that's

-defined everywhere

-has x=13 as its only x intercept 

-has x=1 as a local max which is its only critical point 

Let g(x) = (1/f(x^2-3))^(2)+3

How many zeros does g(x) have? 

g(x) should have no zeros; this is is because (1/f(x^2-3))^2 cannot equal -3 due to the square (this part of the equation must be equal to -3 in order for g(x) to equal 0).   

100

The best quadratic approximation to y=2lnx is given in the form displayed below 

y=ax^2+bx+c 

where a, b, and c are constants. Knowing that this approximation has the same first and second derivatives as y=2lnx at x=1, solve for a.

First, solve for the second derivative of the approximation and of the original function. Then, set each respective second derivative to each other to solve for a; your answer should be -1. 

200

Let the function y(x) be defined implicitly on 0<x<0 by ln(x/e^y)=cos(y).

Find the y coordinate where this curve y(x) has a vertical tangent line for 0<y<pi. 

Find the derivative of y(x) first, then set this equation to undefined (this is because we are trying to find the x value where y(x) has a vertical tangent line). Knowing that y'=1/(x-sin(y)x), the bottom of this equation should equal to 0. Thus, set this equation to 0 and solve for y; your answer should be pi/2. 

200

Let f(x) = sin(x^4) 

Is the function concave up or concave down at x=10? 

f''(x)=12x^2(cos(x^4))+4x^3(4x^3)(-sin(x^4))

f''(x)=4888687.635

The second derivative is positive, therefore the graph of f(x) should be concave up. 

200

Why do none of my jokes work? 

Because they're about unemployed people. 

200

Let f be a differentiable function that's

-defined everywhere

-has x=13 as its only x intercept 

-has x=1 as a local max which is its only critical point 

Let g(x) = (1/f(x^2-3))^(2)+3

How many critical points does g(x) have? 

g(x) should have a total of five different critical points. This is found by first finding the derivative of g(x) then setting it to 0 or undefined. 

The five critical points found should be +/-4, +/-2, and 0. 

200

The best quadratic approximation to y=2lnx is given in the form displayed below 

y=ax^2+bx+c 

where a, b, and c are constants. Knowing that this approximation has the same first and second derivatives as y=2lnx at x=1, solve for b.

First, solve for the first and second derivatives of the original function and its approximation, then solve for a. Knowing that a=-1, set each respective function's first derivative to each other, plug in a, and solve for b. Your answer should be 4. 

300

Let the function y(x) be defined implicitly on 0<x<0 by ln(x/e^y)=cos(y).

Find the x coordinate where this curve y(x) has a vertical tangent line for 0<x<10.

Unfortunately, this x coordinate cannot be solve for using the derivative of y(x). However, if we know the y coordinate where y(x) has a tangent line (which can be solve for using y(x)'s derivative), then we can plug this in into the original function to solve for its corresponding x coordinate. By substituting a y coordinate of pi/2, the resulting x coordinate should be e^pi/2. 

300

Let f(x)=(cos(ktan(x)))/(pi)^(sin(2x)-1) and let the equation of the tangent line to y=f(x) at x=pi/4 be represented by the following: 

y=-{  }ksin({  }k)(x - pi/{  }) + {  }

What value belongs in the third space?

4

300

How do you make holy water? 

You boil the hell out of it. 

300

Let f be a differentiable function that's

-defined everywhere

-has x=13 as its only x intercept 

-has x=1 as a local max which is its only critical point 

Let g(x) = (1/f(x^2-3))^(2)+3

Classify the critical point at 0. 

Before using the first derivative test, sketch a graph of f(x). Afterwards, use the first derivative test to find that the critical point at x=0 is a local minimum. 
300

The best quadratic approximation to y=2lnx is given in the form displayed below 

y=ax^2+bx+c 

where a, b, and c are constants. Knowing that this approximation has the same first and second derivatives as y=2lnx at x=1, solve for c. 

First, solve for a and b by using the first and second derivatives of each respective function. Then, find the corresponding y coordinate to x=1 by substituting 1 as x into the original function. By plugging in this y value, x value, and the a and b value into the linear approximation, c can be solved for, which should equal -3. 

400

Find the rate of change of volume with respect to pressure. The original function is shown below with a, b, n, and R as constants: 

(P+(n^2a/V^2))(V-nb)=nRT

First, distribute the entire given function - this should give you PV-Pnb+(n^2a/V^2)-(n^3ab/V^2)=nRT. Next, take the derivative of this function by using the product and quotient rules; after simplifying this derivative, you should get the answer below: 

V'=(nb-V)/(P-(n^2a/V^2)+(2n^3ab/V^3)

400

Let f(x)=(cos(ktan(x)))/(pi)^(sin(2x)-1) and let the equation of the tangent line to y=f(x) at x=pi/4 be represented by the following: 

y=-{  }ksin({  }k)(x - pi/{  }) + {  }

What value belongs in the fourth space? 

Plug in the x value, pi/4, into the original equation to solve for its corresponding y value, which belongs in the fourth space. You should get 3 as your answer. 

400

Why can you never trust a math teacher holding graphing paper?

They must be plotting something.

400

Let f be a differentiable function that's

-defined everywhere

-has x=13 as its only x intercept 

-has x=1 as a local max which is its only critical point 

Let g(x) = (1/f(x^2-3))^(2)+3

Classify the critical point at x=-2. 

Before using the first derivative test, sketch a graph of f(x) based on the given information. Afterwards, use the first derivative test to find that at x=-2 there is a local maximum.

400

Find the equation of the tangent line at the x-intercept of the curve y(x), where y(x)=ln(x/e^y)=cos(y). 

First, find the coordinates of the x intercept by plugging in 0 for y into the given implicitly defined function. Then, solve for the derivative of its function and plug in 1 into x to find the slope of the tangent line at x=1. The resulting linear approximation should be: y= (1/e)(x-e)+0

500

Let f(x)=(cos(ktan(x)))/(pi)^(sin(2x)-1) and let the equation of the tangent line to y=f(x) at x=pi/4 be represented by the following: 

y=-{  }ksin({  }k)(x - pi/{  }) + {  }

What value belongs in the first and second space?

The first and second space are both a part of the slope of the linear approximation, aka the derivative of f(x). To find this value, begin by solving for the derivative of f(x), then plug in pi/4 into that derivative. A slope of -2ksin(k) should be found; thus the first space is 2 whereas the second is 1. 

500

 What do you call dudes who love math?

AlgeBROS

M
e
n
u