Finding Parallel Tangent Line Points on Curve: y=1/3x^3-4x^2+18x+22

  • Thread starter Thread starter maxpayne_lhp
  • Start date Start date
  • Tags Tags
    Suggestions
Click For Summary
To find the points on the curve y=1/3x^3 - 4x^2 + 18x + 22 where the tangent lines are parallel to the line 6x - 2y = 1, first determine the slope of the given line, which is 3. Next, calculate the derivative of the cubic curve to find the slopes of the tangent lines. Set the derivative equal to 3 and solve the resulting quadratic equation to find the x-values where the tangents are parallel. Finally, substitute these x-values back into the original curve equation to obtain the corresponding y-values. This will yield the two points on the curve where the tangent lines are parallel to the specified line.
maxpayne_lhp
Messages
35
Reaction score
0
Hey... I am kinda got stuck with this problem... can you guys give me a hint or something...

Problem says:

The tangentline to the curve y=1/3 x^3 - 4x^2 + 18x + 22 is parallel to the line 6x - 2y = 1 at 2 points on the curve... find the 2 points.

Well I was thinking about writing the function for another line which has the same lope with the one given... so it should be something like y = 3x + m

Now what?

Thanks for your help.
 
Physics news on Phys.org
You don't need to write an equation for another line, you just have to know what the slope of 6x - 2y = 1 is. Then you need to find an equation for the slopes of the lines tangent to your cubic curve. Then you have to solve (a quadratic) for when the slopes of the tangents equal the slope of 6x - 2y = 1.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

Similar threads

  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 8 ·
Replies
8
Views
2K
Replies
2
Views
1K
  • · Replies 24 ·
Replies
24
Views
3K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
4
Views
5K