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1. General Plan for Investigating Functions and Plotting Their Graphs.
2. Calculate the Area of the Triangle with Vertices A(1;1;1), B(2;3;4), and C(4;3;2).
3. Find Limits Using L'Hopital's Rule: a) $\lim_{x \to 0} \frac{e^x - 1}{\sin(x)}$ b) $\lim_{x \to 0} \frac{e^x - e^{-x}}{\sin(x)\cos(x)}$
4. Differentiate the Given Functions: a) $y = ae^{-b x^2}$ b) $y = \cos(2x \cdot \ln(x))$
5. Find the Total Differential of the Functions: a) $z = \frac{x + y}{x - y}$ b) $z = \sin(xy)$

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