Recent content by tc903

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    Tschirnhausen Curve: Finding Tangents at a Given Point

    Are the given families orthogonal trajectories of each other? $$ {x}^{2}+{y}^{2} = ax $$ $$ {x}^{2}+{y}^{2} = by $$ I first started by finding them implicitly. $$ \frac{2x+a}{2y} = y' $$ $$ \frac{2x+b}{2y} = y' $$ Then the problem wanted me to sketch my answer. The Tschirnhausen, I...
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    How Does a 3% Increase in Radius Affect Blood Flow?

    $$ F = k{R}^{4} $$ The flux F is volume of blood per unit time. This is proportional to the 4th power of the radius R of the blood vessel. All I am given is 3% increase in radius will affect blood flow how. I am to find whether is decreases or increase blood flow and by what percent. $$...
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    Differentiation and Tangent Lines.

    Thanks MarkFl, you were extremely helpful and our answers agree.
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    Differentiation and Tangent Lines.

    I had to leave. Did you mean $$ a{x}^{2}+bx+c = 0 $$ $$ {b}^{2} - 4ac = 0 $$ So that I may find repeated real solutions. $$ {x}^{2} + 4\left({(mx)}^{2}-12{m}^{2}x+3mx-12{m}^{2}+144{m}^{2}-36m+3mx-36m+9\right) = 36 $$ Skipping steps shown. $$...
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    Differentiation and Tangent Lines.

    The second problem. $$ y - {y}_{1} = m\left(x-{x}_{1}\right) $$ $$ y - 3 = m\left(x-12\right) $$ $$ y = m\left(x-12\right) + 3 $$Substituting the above,$$ {x}^{2} + 4{y}^{2} = 36 $$ $$ {x}^{2} +4\left(m\left(x-12\right)+3\right)^{2} = 36 $$ $$ {x}^{2} + 4\left(mx-12m+3\right)^{2} = 36 $$
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    Differentiation and Tangent Lines.

    Alright, here is my work. $$ f(x) = \arctan\left({\frac{\sqrt{1+x}}{\sqrt{1-x}}}\right) $$ $$ \d{f}{x} = \frac{1}{1+{\left(\frac{\sqrt{1+x}}{\sqrt{1-x}}\right)}^{2}}\left[\d{}{x}{\left(\frac{1+x}{1-x}\right)}^{1/2}\right] [/MATh] $$ \d{f}{x} =...
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    Differentiation and Tangent Lines.

    I know what I missed. Thanks MarkFL, I will get back on the second problem soon.
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    Differentiation and Tangent Lines.

    I found $$\d{f}{x}$$ for the first one both using quotient rule and product rule. I changed the latex so it showed my answer now.
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    Differentiation and Tangent Lines.

    Given$$ f(x) = \arctan\left({\frac{\sqrt{1+x}}{\sqrt{1-x}}}\right)$$ I differentiated and this was my answer. $$\d{y}{x} = \frac{1}{2\sqrt{1+x}\sqrt{1-x}{(1-x)}^{2}}$$ I used implicit differentiation on the elliptic curve $${x}^{2}+4{y}^{2} = 36$$ and it wants two horizontal tangents through...
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    Chain rule derivatives for y=a^3+cos^3(x) and y=[x+(x+sin^2(x))^7]^5

    My first question states y=a^3+cos^3 (x) (I couldn't quite figure out latex again.) The derivative using the chain rule I found to be y'=(a^3)(ln a)+3((cos (x))^2)(-sin(x)) = y' = (a^3)(ln a)-3((cos (x))^2)(sin (x)) The second question y=[x+(x+sin^2 (x))^7]^5 Derived using chain rule...
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    The Rock's Height and Velocity: 16t-1.86t^2

    I would think the same, maybe I shouldn't have rounded it to -15.9 when I originally did that way. I have a computer that is telling me no when I plug in an answer like that.
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    Finding limits by rationalizing and from the left

    I should have tried that. I just didnt think it was an option because it didnt say I can put it in their. The question usually asks if the limit exists find it. (type so and so for inifinity or for none exist) It had only chosen one of those. Thanks MarkFL!
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    Finding limits by rationalizing and from the left

    I stated it did not exist, but that is wrong. I substituted zero and that would be make it undefined but that is wrong. It isn't - \infty . It is zero? Here is a table. x,y -1,-6 -2,-3 -3,-2 -4,-3/2 -5,-6/5 -6,-1 -7,-6/7 -8,-3/4 -9,-2/3 -10,-3/5
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    Finding limits by rationalizing and from the left

    Thanks MarkFL. I was wondering if you can clear something up with the second question though with the absolute value.
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    The Rock's Height and Velocity: 16t-1.86t^2

    H=16t-1.86t^2 is the height formula. The ball was thrown 16 m/s. I derived 16-3.72a. When will the rock hit the surface. It hits the surface 8.6 seconds. What velocity does the rock hit the surface? H=0.0344 then the velocity is 15.87 m/s? This is what I chose. [-4.-2) (-2,2) [2,4) (4,6) (6,8)