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Category: Algebra

In-ABC-the-following-relationship-holds-cyc-a-2-b-2-c-2-4-cyc-cos-A-2-

Question Number 176365 by Shrinava last updated on 16/Sep/22 $$\mathrm{In}\:\:\bigtriangleup\mathrm{ABC}\:\:\mathrm{the}\:\mathrm{following}\:\mathrm{relationship}\:\mathrm{holds}: \\ $$$$\underset{\boldsymbol{\mathrm{cyc}}} {\sum}\:\frac{\mathrm{a}^{\mathrm{2}} }{\mathrm{b}^{\mathrm{2}} \:+\:\mathrm{c}^{\mathrm{2}} }\:+\:\mathrm{4}\:\underset{\boldsymbol{\mathrm{cyc}}} {\prod}\:\mathrm{cos}\:\mathrm{A}\:\leqslant\:\mathrm{2} \\ $$ Answered by behi834171 last updated on…

if-x-1-a-a-2-a-3-y-1-b-b-2-b-3-prove-that-1-ab-a-2-b-2-a-3-b-3-xy-x-y-1-

Question Number 45283 by peter frank last updated on 11/Oct/18 $$\boldsymbol{\mathrm{if}}\:\boldsymbol{\mathrm{x}}=\mathrm{1}+\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{a}}^{\mathrm{2}} +\boldsymbol{\mathrm{a}}^{\mathrm{3}} +\ldots\ldots\ldots \\ $$$$\:\:\:\:\boldsymbol{\mathrm{y}}=\mathrm{1}+\boldsymbol{\mathrm{b}}+\boldsymbol{\mathrm{b}}^{\mathrm{2}} +\boldsymbol{\mathrm{b}}^{\mathrm{3}} +\ldots\ldots\ldots \\ $$$$\boldsymbol{\mathrm{prove}}\:\boldsymbol{\mathrm{that}} \\ $$$$\mathrm{1}+\boldsymbol{\mathrm{ab}}+\boldsymbol{\mathrm{a}}^{\mathrm{2}} \boldsymbol{\mathrm{b}}^{\mathrm{2}} +\boldsymbol{\mathrm{a}}^{\mathrm{3}} \boldsymbol{\mathrm{b}}^{\mathrm{3}} +\ldots\ldots\ldots=\frac{\boldsymbol{\mathrm{xy}}}{\boldsymbol{\mathrm{x}}+\boldsymbol{\mathrm{y}}−\mathrm{1}}…

What-is-the-he-minimum-value-of-x-2-1-y-x-2-25-z-y-2-4-9-z-2-16-if-x-y-and-z-R-

Question Number 110799 by dw last updated on 30/Aug/20 $$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:{What}\:{is}\:{the}\:{he}\:{minimum}\:{value}\:{of}\: \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\sqrt{{x}^{\mathrm{2}} +\mathrm{1}}+\sqrt{\left({y}−{x}\right)^{\mathrm{2}} +\mathrm{25}}+\sqrt{\left({z}−{y}\right)^{\mathrm{2}} +\mathrm{4}}+\sqrt{\left(\mathrm{9}−{z}\right)^{\mathrm{2}} +\mathrm{16}} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:{if}\:\:\left({x},\:{y}\:{and}\:{z}\right)\:\in\:\mathbb{R}\: \\ $$ Terms of Service Privacy Policy…

Question-176303

Question Number 176303 by infinityaction last updated on 16/Sep/22 Answered by cortano1 last updated on 16/Sep/22 $$\:\mathrm{let}\:\begin{cases}{{a}+{b}={x}}\\{{c}+{d}={y}}\end{cases}\Rightarrow{x}+{y}=\mathrm{2}\:;\:\mathrm{y}=\mathrm{2}−\mathrm{x} \\ $$$$\:\mathrm{M}=\mathrm{f}\left(\mathrm{x}\right)=\:\mathrm{x}\left(\mathrm{2}−\mathrm{x}\right)=\mathrm{2x}−\mathrm{x}^{\mathrm{2}} \:;\:\mathrm{x}\geqslant\mathrm{0} \\ $$$$\Rightarrow\mathrm{0}\leqslant\mathrm{f}\left(\mathrm{x}\right)\leqslant\mathrm{1} \\ $$$$\Rightarrow\mathrm{0}\leqslant\:\mathrm{M}\leqslant\mathrm{1} \\…