Category: Algebra

Question Number 120480 by mathocean1 last updated on 31/Oct/20 $$showthat\mathrm{\forall }n\in {\mathbb{N}}^{\ast }$$$$\sum _{k=1}^{n}k(n-k)=\frac{(n-1)(n+1)}{6}$$ Answered by Ar Brandon last updated on 31/Oct/20 $$\mathrm{S}_{\mathrm{k}}…

Question Number 120472 by mathocean1 last updated on 31/Oct/20 $$A=\overline{5x23}{}^{6}showthatA\equiv x-4\left[7\right]$$$$deductthevalueofxforwhichAis$$$$divisibleby7$$ Terms of Service Privacy Policy Contact: info@tinkutara.com

Question Number 120471 by mathocean1 last updated on 31/Oct/20 $$solvein\mathbb{Z}{x}^3+2x+1\equiv 1\left[4\right]$$ Answered by Ar Brandon last updated on 31/Oct/20 $$\mathrm{x}^{\mathrm{3}} +\mathrm{2x}+\mathrm{1}=\mathrm{1}\left[\mathrm{4}\right]\Rightarrow\mathrm{x}^{\mathrm{3}} +\mathrm{2x}=\mathrm{0}\left[\mathrm{4}\right] \…

Question Number 120464 by pooooop last updated on 31/Oct/20 Answered by Jamshidbek2311 last updated on 31/Oct/20 $$\sqrt{x-1}=a\Rightarrow x=a^2+1$$$$\sqrt{y-4}=b\Rightarrow y=b^2+4$$$$\sqrt{{z}−\mathrm{9}}={c}\:\Rightarrow\:{z}={c}^{\mathrm{2}} +\mathrm{9}\: \…

Question Number 54923 by mr W last updated on 14/Feb/19 $$Is\tan 1°rationalorirrational?$$$$Giveyourproof.$$ Commented by Otchere Abdullai last updated on 14/Feb/19 $${tan}\mathrm{1}°\:=\mathrm{0}.\mathrm{01745506493} \…