Cho đồ thị hàm số <span class="MathJax_Preview" style="color: inherit; display: none;"></span><span id="MathJax-Element-1-Frame" class="mjx-chtml MathJax_CHTML" tabindex="0" data-mathml="<math xmlns="http://www.w3.org/1998/Math/MathML"><mstyle mathsize="1.44em"><mi>y</mi><mo>=</mo><msup><mi>a</mi><mrow class="MJX-TeXAtom-ORD"><mi>x</mi></mrow></msup><mo>,</mo></mstyle></math>" role="presentation" style="font-size: 127%; position: relative;"><span id="MJXc-Node-1" class="mjx-math" aria-hidden="true"><span id="MJXc-Node-2" class="mjx-mrow"><span id="MJXc-Node-3" class="mjx-mstyle"><span id="MJXc-Node-4" class="mjx-mrow" style="font-size: 144%;"><span id="MJXc-Node-5" class="mjx-mi"><span class="mjx-char MJXc-TeX-math-I" style="padding-top: 0.199em; padding-bottom: 0.495em; padding-right: 0.006em;">y</span></span><span id="MJXc-Node-6" class="mjx-mo MJXc-space3"><span class="mjx-char MJXc-TeX-main-R" style="padding-top: 0.101em; padding-bottom: 0.298em;">=</span></span><span id="MJXc-Node-7" class="mjx-msubsup MJXc-space3"><span class="mjx-base"><span id="MJXc-Node-8" class="mjx-mi"><span class="mjx-char MJXc-TeX-math-I" style="padding-top: 0.199em; padding-bottom: 0.298em;">a</span></span></span><span class="mjx-sup" style="font-size: 70.7%; vertical-align: 0.513em; padding-left: 0px; padding-right: 0.071em;"><span id="MJXc-Node-9" class="mjx-texatom" style=""><span id="MJXc-Node-10" class="mjx-mrow"><span id="MJXc-Node-11" class="mjx-mi"><span class="mjx-char MJXc-TeX-math-I" style="padding-top: 0.199em; padding-bottom: 0.298em;">x</span></span></span></span></span></span><span id="MJXc-Node-12" class="mjx-mo"><span class="mjx-char MJXc-TeX-main-R" style="margin-top: -0.145em; padding-bottom: 0.544em;">,</span></span></span></span></span></span><span class="MJX_Assistive_MathML" role="presentation"><math xmlns="http://www.w3.org/1998/Math/MathML"><mstyle mathsize="1.44em"><mi>y</mi><mo>=</mo><msup><mi>a</mi><mrow class="MJX-TeXAtom-ORD"><mi>x</mi></mrow></msup><mo>,</mo></mstyle></math></span></span><script type="math/tex" id="MathJax-Element-1">\Large y = a^{x},</script> <span class="MathJax_Preview" style="color: inherit; display: none;"></span><span id="MathJax-Element-2-Frame" class="mjx-chtml MathJax_CHTML" tabindex="0" data-mathml="<math xmlns="http://www.w3.org/1998/Math/MathML"><mstyle mathsize="1.44em"><mi>y</mi><mo>=</mo><msup><mi>b</mi><mrow class="MJX-TeXAtom-ORD"><mi>x</mi></mrow></msup><mo>,</mo></mstyle></math>" role="presentation" style="font-size: 127%; position: relative;"><span id="MJXc-Node-13" class="mjx-math" aria-hidden="true"><span id="MJXc-Node-14" class="mjx-mrow"><span id="MJXc-Node-15" class="mjx-mstyle"><span id="MJXc-Node-16" class="mjx-mrow" style="font-size: 144%;"><span id="MJXc-Node-17" class="mjx-mi"><span class="mjx-char MJXc-TeX-math-I" style="padding-top: 0.199em; padding-bottom: 0.495em; padding-right: 0.006em;">y</span></span><span id="MJXc-Node-18" class="mjx-mo MJXc-space3"><span class="mjx-char MJXc-TeX-main-R" style="padding-top: 0.101em; padding-bottom: 0.298em;">=</span></span><span id="MJXc-Node-19" class="mjx-msubsup MJXc-space3"><span class="mjx-base"><span id="MJXc-Node-20" class="mjx-mi"><span class="mjx-char MJXc-TeX-math-I" style="padding-top: 0.495em; padding-bottom: 0.298em;">b</span></span></span><span class="mjx-sup" style="font-size: 70.7%; vertical-align: 0.513em; padding-left: 0px; padding-right: 0.071em;"><span id="MJXc-Node-21" class="mjx-texatom" style=""><span id="MJXc-Node-22" class="mjx-mrow"><span id="MJXc-Node-23" class="mjx-mi"><span class="mjx-char MJXc-TeX-math-I" style="padding-top: 0.199em; padding-bottom: 0.298em;">x</span></span></span></span></span></span><span id="MJXc-Node-24" class="mjx-mo"><span class="mjx-char MJXc-TeX-main-R" style="margin-top: -0.145em; padding-bottom: 0.544em;">,</span></span></span></span></span></span><span class="MJX_Assistive_MathML" role="presentation"><math xmlns="http://www.w3.org/1998/Math/MathML"><mstyle mathsize="1.44em"><mi>y</mi><mo>=</mo><msup><mi>b</mi><mrow class="MJX-TeXAtom-ORD"><mi>x</mi></mrow></msup><mo>,</mo></mstyle></math></span></span><script type="math/tex" id="MathJax-Element-2">\Large y = b^{x},</script> $\Large y =

Cho đồ thị hàm số y=ax, y=bx, $\Large y =

4.8/5

Tác giả: Thầy Tùng

Đăng ngày: 18 Aug 2022

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Hình minh họa Cho đồ thị hàm số $\Large y = a^{x},$ $\Large y = b^{x},$ $\Large y =

Câu hỏi:

Cho đồ thị hàm số y=ax, y=bx, y=cx (a,b,c dương và khác 1). Chọn đáp án đúng.

Hình câu hỏi 1. Cho đồ thị hàm số $\Large y = a^{x},$ $\Large y = b^{x},$ $\Large y =

Đáp án án đúng là: A

Lời giải chi tiết:

Chọn A

Dựa vào đồ thị ta thấy:

Hàm số y=cx là nghịch biến nên c<1.

Hàm số y=ax, y=bx đồng biến nên a>1, b>1.

Mặt khác hàm số y=bx tăng nhanh hơn  y=ax trên miền  x>0 nên  b>a.

Do đó b>a>c.