<span> y=kx+9 </span><span>А(-2;7)
</span>7=k*(-2)+9
7-9= -2k
-2=-2k
k=1
<span>cos 107° cos 17° + sin107° sin17<span>°=cos(107-17)=cos90=0
cos36</span>° cos24° - sin36° sin24<span>°=cos(36+24)=cos60=1/2
sin63</span>° cos27°+ cos63° sin27<span>°=sin(63+27)=sin90=1</span></span>
Два........................................
Y=cos(x)/(2x+3)
y'=(-sin(x)*(2x+3)-2*cos(x))/(2x+3)^2