If a virus spreads at a rate that can be modeled by the exponential function \( A(t)=a^{r t} \), how many people will be infected after 5 days if initially 3 people are infected and the growth rate is \( 40 \% \) ? (Use your calculator for a precise version of e. If you are not able to use a calculator, you can approximate e as 2.718 . Round your anșwer to the nearest person.)

\( a _ { n } ) : 1 , \frac { 1 } { 1 + 2 } , \frac { 1 } { 1 + 2 + 3 } , \cdots , \frac { 1 } { 1 + 2 + 3 + \cdots + n } \)

mple 2.19 Show that \( 5^{n}+6^{n}<9^{n} \) for \( n \geq 2 \)

If \( f(x)=\frac{\sqrt{x+2}}{3-3 x^{2}} \), for which values of \( x \) is \( 1.22 \quad f(x) \) non real \( 1.23 \quad f(x) \) undefined \( 12.4 \quad f(x)>0 \)

5. \( \forall \alpha \in \mathbb{R} \) için, \( A=-2 \sin \alpha+1 \) olduğuna göre, A nın değer aralığı nedir?

I On donne le nombre complexe \( u= \) 1)a) calculer \( u^{2} \) et \( u^{4} \) b) calculer le module et un argument de de \( u \) 2) le plan complexe est muni d'un coordonnées \( (x, y) \) du plan, on associe s Déterminer l'ensemble des points \( M \) du \( u \times z \) est égal à 8 . II) Linéariser \( : A=\sin 3 x \cos ^{2} x ; B=c \)