Recent content by lamerali

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    Derivatives (Trig) with Isosceles Triangles

    The base of an isosceles triangle is 20 cm and the altitude is increasing at the rate of 1 cm/min. At what rate is the base angle increasing when the area is 100 cm2? Hmmmm...I have the same question but i came up with a completely different answer...is this anywhere near correct? The...
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    Derivatives of trig functions and isosceles triangles.

    is the rest of this equation anywhere near correct?? :(
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    Checking derivatives of trigonometric functions with chain and product rules

    Thank you sooo much! couldn't have done that without you! THANKS for alllll the help! :D
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    Derivatives of trig functions and isosceles triangles.

    but if i plug in A = (1/2) b x h 100 = (1/2) (20) h h is still equal to 10 cm. Is that the only error you see? because that does not effect the rest of the equation...:S
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    Derivatives of trig functions and isosceles triangles.

    The base of an isosceles triangle is 20 cm and the altitude is increasing at the rate of 1 cm/min. At what rate is the base angle increasing when the area is 100 cm2? I wasnt really sure where to start on this question so i tried my best at an answer. I'm sure I've gone wrong with this...
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    Checking derivatives of trigonometric functions with chain and product rules

    okey i believe i figured question 5 out: y = \frac{1}{1+tanx} y1 = (1 + tanx)^{-1} = (-1)(1 + tanx)(sec^{-2} sec ^{2} x = - \frac{(sec^2)x}{(1 + tanx)^2} I am still unsure where i am going with question 4 but here is my zillionth attempt :D y = tan^{2}(cos x) my answer...
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    Checking derivatives of trigonometric functions with chain and product rules

    also are question five and six okay? i don't see how i can come up with any other solutions.
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    Checking derivatives of trigonometric functions with chain and product rules

    alright...i'm not sure i got this one but here it goes: y = tan ^{2} (cos x) y1 = 2tan cosx + 2 sec^{2}cosx - sin tan^{2} how does it look? :|
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    Checking derivatives of trigonometric functions with chain and product rules

    great thank you! as for question 3 y = 2x( \sqrt{x} - cotx) my second attempt at an answer: y1 = 2( \sqrt{x} - cotx) + 2x(\frac{1}{2} x^{- \frac{1}{2}} + csc^{2} x = 2( \sqrt{x} - cotx) + \sqrt{x} + 2x csc^{2} x is this anywhere near correct? thanks i am not sure how to...
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    Checking derivatives of trigonometric functions with chain and product rules

    so would question 2 be... 4 cos^{2} (\pi x) 12 cos ^{2} (\pi x) (-sin (\pi x)) (\pi) (-sin (\pi x)) 12 \pi cos ^{2} (\pi x)
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    Checking derivatives of trigonometric functions with chain and product rules

    Hi, I'm working with finding the derivatives of trigonometric functions but I'm not confidant with some of my answers. if someone would go over these derivatives i would appreciate it. thanks in advance! determine \frac{dy}{dx} . do not simplify. question 1 y = sec \sqrt[3]{x} my...
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    Evaluating limits involving sin x, cos x, and tan x

    Thannnnnnnk you tiny tim! question 1, 2, and 3 are completely clear, i believe i came up with the correct answer. :D However I'm still unsure of question 4. Even if you plug in x = 0 into \frac{sin cosx}{sec x} where sec x is equal to \frac{1}{cos x} my answer comes to 0.84147, also if you...
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    Evaluating limits involving sin x, cos x, and tan x

    Hello, i'm having some trouble with evaluating limits if anyone could help me out a bit i would appreciate it. thanks in advance evaluate the following limits: Question 1: lim x -> 0 \frac{2tan^{2}x}{x^{2}} my answer: u = x^{2} as x -> 0 u-> 0 = lim u->0...