1. (a+b)c=ac+bc
<span>2. (a-b)c=ac-ab</span>
1,2 : 36 ≈ 0,03
1234567890-=
sin5x-sin3x=0
2sinxcos4x=0
1) sinx=0 , x =<span>πn, </span>
<span>2) cos4x=0, 4x=<span>π/2 +<span>πn, x=<span>π/8+<span>π/4n</span></span></span></span></span>
При х=1:
3*1^2+6*1-9=3-6+9=0