Решение. Способ 1<span><span>f′</span>(x)=<span><span>(<span><span>4⋅x−7 / </span><span>x2</span></span>)</span>′</span>=
</span><span>=(<span><span><span><span>(4⋅x−7)</span>′</span>⋅<span>x2</span>−<span>(4⋅x−7)</span>⋅<span><span>(<span>x2</span>))</span>′ / </span></span><span><span>(<span>x2</span>)</span>2</span></span>=
</span><span>=<span><span><span><span>(4⋅x)</span>′</span>⋅<span>x2</span>−<span>(4⋅x−7)</span>⋅2⋅x</span><span><span>(<span>x2</span>)</span>2</span></span>=
</span><span>=<span><span>4⋅<span>x2</span>−<span>(4⋅x−7)</span>⋅2⋅x / </span><span><span>(<span>x2</span>)</span>2
</span></span></span>Ответ:<span>f′</span>(x)=<span><span>4⋅<span>x2</span>−<span>(4⋅x−7)</span>⋅2⋅x / </span><span><span>(<span>x2</span>)</span><span>2</span></span></span>
Думаю, всё правильно) в принципе не сложное задание.
1) нет
2) нет
3) да
4) нет
5) да
6) ?
7) нет
8) да
9) нет
10) возможно да
11) да
12) нет
13) да
14) да
15) нет
6/x-3/2x; x=-1,8
6/(-1,8)-3/2*(-1,8)=-6/1,8+3/3,6
=-12+3/3,6=-9/3,6=-2,5 будет правильный ответ
X₁=√2
x₂=-√8
ах²+bx+c=0
По т.Виета
x₁+x₂=- b/a √2+(-√8)= -b/a √2-√8=-b/a √2-2√2=-b/a -√2=-b/a √2=b/a
x₁*x₂= c/a √2*(-√8)=c/a -√16=c/a -4=c/a -4=c/a -4=c/a
При а=1 b=√2
-4=c
x²+√2 * x-4=0