MATEMATICA - Um quinto dos alunos de uma classe usa óculos. Dentre os alunos que usam óculos, um quarto são meninas. Sabe- se ainda que seis meninos usam óculos. Quantos sāo os alunos dessa classe? a) 30 alunos. b) 36 alunos. c) 40 alunos. d) 44 alunos. e) 50 alunos.

\( \begin{array}{ll}6.1 .1 . & y=\sqrt{7 x}+e^{-x}+\sin e \cdot \cos x+x \ln x \\ 6.1 .2 . & y=\sqrt{x^{2}-\sqrt{1+4 x}}+\tan \left(4-x^{2}\right) \\ 6.1 .3 . & \sin (\pi-x)+y^{2} \cos x=y+4 \\ 6.2 . & \text { Use logarithmic differentiation to find } \frac{d y}{d x} \text { if } y=x^{3}\left[2-x^{2}\right]^{1+x^{2}}\end{array} \)

The area of a circle increases at a rate of \( 5 \mathrm{~cm}^{2} / \mathrm{s} \). a. How fast is the radius changing when the radius is 6 cm ? b. How fast is the radius changing when the circumference is 1 cm ?

Ex. 3 : Évaluer les limites suiv a) \( \lim _{x \rightarrow 2} \frac{\sqrt{2}-\sqrt{x}}{x^{2}-3 x+2} \)

7. \( 11 a x-121 a^{2} x+33 a^{3} \) 8. \( 9 a^{5} b-12 a^{2} b^{3}+15 a b^{2}-18 a \) 9. \( 9 x^{2}+6 x+3 \) 10. \( 4 x^{4}-8 x^{3}+12 x^{2} \)

Graph the line with slope \( \frac{1}{0} \) passing through the point \( (4,3) \)