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1) (2a³x + 5a²x² - 5ax³ + 3x⁴) * (- 3ax²) = - 6a⁴x³ - 15a³x⁴ + 15a²x⁵ - 9ax⁶
2) 3x(x + 6) - (2x - 2)(x + 4) = 3x² + 18x - 2x² - 8x + 2x + 8 = x² +12x +8
Как то так)))
<span>sin3x+sin5x+2sin²(x/2)=1</span>
<span>2sin4x•cosx=1-2sin²(x/2)</span>
<span>2sin4x•cosx=cosx</span>
<span>cosx•(2sin4x-1)=0</span>
<span>1) cosx=0 => x=π/2+πn</span>
<span>2) sin4x=½ => 4x=(-1)^n•π/6+πn => x=(-1)^n•π/24+(π/4)•n</span>