(bc-bc+c^2)/b(b-c)*b^2/c^2=c^2/b(b-c)*b^2/c^2=b/(b-c)
Х= (5п/12)+ пк; х= (7п/12)+пк
A) (7-2х-х^2)-(х-2)(х+3)=
7-2х-х^2-х^2-3х+2х+6=
-2х^2-3х+13=2х^2+3х-13
б) (3m^2+3n^2)-(2m+n)(m+2n)=
3m^2+3n^2-2m^2-4mn-mn-2n^2=
m^2+n^2-5mn
1) 2cos5x-sqrt{3}=0
<span>2)2sin+</span>frac{x}{4}1=0
<span>3)sqrt{2}(frac{pi}{6}-4x)+1=0</span>
<span>4)-2tg(-frac{3x}{2}=2</span>
5)cosx cos2x-sinx sin2x=-1
<span>6)<span>frac{2sinx+sqrt{3}}{cos8x-8}=0</span></span>
<span>1) cos5x = /25x = +- П/6 +2Пkx = +-П/30 +2Пk/5 2,3 - не поняла запись (там не всего хватает) 4) 5) cosx <span>6) </span></span>