\ \frac{sina}{cosa}=2\ =>\ sina=2cosa\\
*=\frac{8*2cosa-9cosa}{6cosa-7*2cosa}=\frac{7cosa}{-8cosa}=-\frac{7}{8}\\
b)\ \frac{sina+2cosa}{4cosa-3sina}=5\\
4cosa-3sina \neq 0\ =>\ 3sina\neq 4cosa\ =>\frac{sina}{cosa}\neq \frac{4}{3}\ => \\
=>\ tga \neq \frac{4}{3}\\
sina+2cosa=5*(4cosa-3sina)\\
sina+2cosa=20cosa-15sina\\
16sina=18cosa\\
\frac{sina}{cosa}=\frac{18}{16}\\
tga=1\frac{1}{8}" alt="a) \ \frac{8sina-9cosa}{6cosa-7sina}\ =*\\
tga=2=>\ \frac{sina}{cosa}=2\ =>\ sina=2cosa\\
*=\frac{8*2cosa-9cosa}{6cosa-7*2cosa}=\frac{7cosa}{-8cosa}=-\frac{7}{8}\\
b)\ \frac{sina+2cosa}{4cosa-3sina}=5\\
4cosa-3sina \neq 0\ =>\ 3sina\neq 4cosa\ =>\frac{sina}{cosa}\neq \frac{4}{3}\ => \\
=>\ tga \neq \frac{4}{3}\\
sina+2cosa=5*(4cosa-3sina)\\
sina+2cosa=20cosa-15sina\\
16sina=18cosa\\
\frac{sina}{cosa}=\frac{18}{16}\\
tga=1\frac{1}{8}" align="absmiddle" class="latex-formula">