См скриншот
================================
да, без проблем)
y'=(1/cos^2x) * 3
Вот посмотри_)))это обычное линейное уравнение
<span><span>{<span><span>4x−3y=12
</span><span><span>4/3</span>x−y=4</span></span></span>⇒
</span><span><span>
{<span><span>4x−3y=12
</span><span>y=<span>43</span>x−4</span></span></span>⇒
</span><span><span>
{<span><span>4x−3<span>(<span>43</span>x−4)</span>=12
</span><span>y=<span>43</span>x−4</span></span></span>⇒
</span><span><span>
{<span><span>0=0</span><span>y=<span>43
</span>x−4</span></span></span>⇒
</span><span>Получили верное равенство для любого </span>xОтвет: <span><span>(x;<span>43</span>x−4),x∈R</span></span>
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