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Category: Algebra

Question-56042

Question Number 56042 by Tawa1 last updated on 09/Mar/19 Answered by math1967 last updated on 09/Mar/19 $$\overset{{n}} {{c}}_{{r}} =\frac{{n}!}{{r}!\left({n}−{r}\right)!}×\frac{\left({n}−{r}+\mathrm{1}\right)}{\left({n}−{r}+\mathrm{1}\right)}=\frac{{n}!×\left({n}−{r}+\mathrm{1}\right)}{{r}×\left({r}−\mathrm{1}\right)!\left({n}−{r}+\mathrm{1}\right)!}\: \\ $$$$=\frac{{n}!}{\left({r}−\mathrm{1}\right)!\left({n}−{r}+\mathrm{1}\right)!}×\left[\frac{{n}−{r}+\mathrm{1}}{{r}}\right] \\ $$$$=\overset{{n}} {\:}{c}_{{r}−\mathrm{1}} \left[\frac{\left({n}−{r}+\mathrm{1}\right)}{{r}}\right]…

Question-121538

Question Number 121538 by Khalmohmmad last updated on 09/Nov/20 Answered by benjo_mathlover last updated on 09/Nov/20 $$\left(\mathrm{i}\right)\:\mid\mathrm{2x}^{\mathrm{2}} +\mathrm{3x}−\mathrm{2}\mid\:=\:\mid\left(\mathrm{2x}−\mathrm{1}\right)\left(\mathrm{x}+\mathrm{2}\right)\mid \\ $$$$\:\:\:\rightarrow\begin{cases}{\mathrm{2x}^{\mathrm{2}} +\mathrm{3x}−\mathrm{2}\:;\:\mathrm{if}\:\mathrm{x}\leqslant−\mathrm{2}\:\cup\:\mathrm{x}\geqslant\frac{\mathrm{1}}{\mathrm{2}}}\\{−\mathrm{2x}^{\mathrm{2}} −\mathrm{3x}+\mathrm{2}\:;\:\mathrm{if}\:−\mathrm{2}\leqslant\mathrm{x}\leqslant\frac{\mathrm{1}}{\mathrm{2}}}\end{cases} \\ $$$$\left(\mathrm{ii}\right)\:\mid\mathrm{x}−\mathrm{2}\mid\:\rightarrow\begin{cases}{\mathrm{x}−\mathrm{2}\:;\:\mathrm{if}\:\mathrm{x}>\mathrm{2}}\\{−\mathrm{x}+\mathrm{2}\:;\:\mathrm{if}\:\mathrm{x}<\mathrm{2}}\end{cases} \\…

solve-for-x-amp-y-x-logy-4-xy-40-

Question Number 55969 by Muhammad bello last updated on 07/Mar/19 $$\:\:\:\boldsymbol{\mathrm{solve}}\:\:\:\boldsymbol{\mathrm{for}}\:\:\:\boldsymbol{\mathrm{x}}\:\:\:\&\:\:\boldsymbol{\mathrm{y}} \\ $$$$\:\:\:\: \\ $$$$\:\:\:\:\boldsymbol{\mathrm{x}}^{\boldsymbol{\mathrm{logy}}} \:\:\:=\:\:\mathrm{4} \\ $$$$\:\: \\ $$$$\:\:\:\:\boldsymbol{\mathrm{xy}}\:\:\:\:=\:\:\:\:\mathrm{40}\: \\ $$ Answered by MJS…

Question-55954

Question Number 55954 by Easyman32 last updated on 06/Mar/19 Answered by MJS last updated on 06/Mar/19 $$\mathrm{draw}\:\mathrm{them}:\:\mathrm{2}\:\mathrm{half}\:\mathrm{parabolas}\:\Rightarrow \\ $$$$\Rightarrow\:\mathrm{1}\:\mathrm{intersection} \\ $$$${x}=\mathrm{11}.\mathrm{932};\:{y}=\mathrm{16}.\mathrm{546} \\ $$ Commented by…

Prove-that-1-A-A-1-

Question Number 55942 by Tawa1 last updated on 06/Mar/19 $$\mathrm{Prove}\:\mathrm{that}:\:\:\:\:\:\frac{\mathrm{1}}{\mid\boldsymbol{\mathrm{A}}\mid}\:\:=\:\:\boldsymbol{\mathrm{A}}^{\mathrm{1}} \\ $$ Commented by 121194 last updated on 06/Mar/19 $$\mathrm{what}\:\mathrm{A}? \\ $$ Terms of Service…

a-3-b-4-c-5-3a-c-42-b-how-is-solution-

Question Number 187008 by mustafazaheen last updated on 12/Feb/23 $$\frac{{a}}{\mathrm{3}}=\frac{{b}}{\mathrm{4}}=\frac{{c}}{\mathrm{5}}\:\:\:\:\:\:\:\:\:\:\:\mathrm{3}{a}+{c}=\mathrm{42}\:\:\:\:\:\:\:\:{b}=? \\ $$$${how}\:{is}\:{solution} \\ $$ Answered by HeferH last updated on 12/Feb/23 $$\frac{{a}}{\mathrm{3}}\:=\:\frac{{c}}{\mathrm{5}} \\ $$$$\:\frac{{a}}{{c}}\:=\:\frac{\mathrm{3}}{\mathrm{5}}\:;\:{a}\:=\:\mathrm{3}{k}\:,\:{c}\:=\:\mathrm{5}{k}\: \\…

Question-121446

Question Number 121446 by mr W last updated on 08/Nov/20 Answered by liberty last updated on 08/Nov/20 $$\mathrm{u}\:=\:\mathrm{x}+\sqrt{\mathrm{1}+\mathrm{x}^{\mathrm{2}} } \\ $$$$\mathrm{u}\left(\mathrm{y}+\sqrt{\mathrm{1}+\mathrm{y}^{\mathrm{2}} }\:\right)\:=\:\mathrm{1}\:\Rightarrow\sqrt{\mathrm{1}+\mathrm{y}^{\mathrm{2}} }\:=\:\frac{\mathrm{1}}{\mathrm{u}}−\mathrm{y} \\ $$$$\Rightarrow\mathrm{1}+\mathrm{y}^{\mathrm{2}}…

x-y-3-x-5-y-5-33-

Question Number 121449 by liberty last updated on 08/Nov/20 $$\:\:\begin{cases}{\mathrm{x}+\mathrm{y}=\mathrm{3}}\\{\mathrm{x}^{\mathrm{5}} +\mathrm{y}^{\mathrm{5}} =\mathrm{33}}\end{cases} \\ $$ Commented by Dwaipayan Shikari last updated on 08/Nov/20 $${x}=\mathrm{1}{or}\:\mathrm{2} \\ $$$${y}=\mathrm{2}\:{or}\:\mathrm{1}\:\:\:\:\:\:\left({By}\:{inspection}\right)…