I done these problems, can anyone tell me if it's right or wrong? Thanks(adsbygoogle = window.adsbygoogle || []).push({});

1) Compute lim (as x approaches 2) of (3x sin(pi x) + cos (pi x))

I got:1

2) Use the derivative rule to find 1/(x-4)

I got:-1/((x+h-4)(x-4))

3) Find an equation for the tangent line to the graph given by:

2x^2 + xy - 4y^2 = 2

at the point where (x,y) = (2, -1)

I got:y = -(7/10)x + (2/5)

4) A 5 foot girl is walking towards a 24 foot lamppost at the rate of 7 feet per second. At what speed is the tip of her shadow moving when she is 8 feet from the lampost?

I got:(168/19) feet per second

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# Homework Help: Calculus Help

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