Help meeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

Question

Help meeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
help-meeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

in progress 0
Khánh Gia 10 months 2020-11-21T07:51:45+00:00 1 Answers 43 views 0

Answers ( )

    0
    2020-11-21T07:52:49+00:00

    Đáp án:

     \(m \geq \dfrac{192\sqrt{2}}{11}\)

    Giải thích các bước giải:

     TXĐ: D=R

    \(y’=-24\sqrt{2}.\cos 8x -11m+3\)

    Để hàm số nghịch biến trên R : 

    \(y’ \leq 0\)

    \(\Leftrightarrow -24\sqrt{2}.\cos 8x -11m+3 \leq 0\)

    \(\Leftrightarrow 11m \geq -24\sqrt{2}\cos 8x+3=h(x)\) \(\forall x \epsilon R\)

    \(\Rightarrow 11m \geq max_{h(x)}\)

    \(h'(x)=192\sqrt{2}.\sin 8x\)

    Ta có: \(-1 \leq \sin 8x \leq 1\)

    \(\Leftrightarrow -192\sqrt{2} \leq 192\sqrt{2}\sin 8x \leq 192\sqrt{2}\)

    \(\Rightarrow max_{h(x)}=192\sqrt{2}\)

    \(\Leftrightarrow 11m \geq 192\sqrt{2}\)

    \(\Leftrightarrow m \geq \dfrac{192\sqrt{2}}{11}\)

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )