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Category: Arithmetic

evaluate-P-n-a-sin-a-sin-2-a-sin-2-2-a-sin-2-n-with-a-1-

Question Number 191229 by mr W last updated on 22/Apr/23 $${evaluate} \\ $$$${P}_{{n}} =\left({a}+\mathrm{sin}\:\theta\right)\left({a}+\mathrm{sin}\:\frac{\theta}{\mathrm{2}}\right)\left({a}+\mathrm{sin}\:\frac{\theta}{\mathrm{2}^{\mathrm{2}} }\right)…\left({a}+\mathrm{sin}\:\frac{\theta}{\mathrm{2}^{{n}} }\right) \\ $$$${with}\:\mid{a}\mid\leqslant\mathrm{1} \\ $$ Terms of Service Privacy Policy…

Show-that-1-2-cos-x-cos-2x-cos-nx-sin-n-1-2-x-2-sin-1-2-x-By-principle-of-mathematical-induction-

Question Number 60155 by Tawa1 last updated on 18/May/19 $$\mathrm{Show}\:\mathrm{that}: \\ $$$$\:\:\:\:\:\:\:\:\:\frac{\mathrm{1}}{\mathrm{2}}\:+\:\mathrm{cos}\left(\mathrm{x}\right)\:+\:\mathrm{cos}\left(\mathrm{2x}\right)\:+\:…\:+\:\mathrm{cos}\left(\mathrm{nx}\right)\:\:=\:\:\frac{\mathrm{sin}\left(\mathrm{n}\:+\:\frac{\mathrm{1}}{\mathrm{2}}\right)\mathrm{x}}{\mathrm{2}\:\mathrm{sin}\left(\frac{\mathrm{1}}{\mathrm{2}}\right)\mathrm{x}} \\ $$$$\mathrm{By}\:\mathrm{principle}\:\mathrm{of}\:\mathrm{mathematical}\:\mathrm{induction} \\ $$ Answered by Kunal12588 last updated on 18/May/19 $$\:{P}\left({n}\right):\frac{\mathrm{1}}{\mathrm{2}}\:+\:\mathrm{cos}\left(\mathrm{x}\right)\:+\:\mathrm{cos}\left(\mathrm{2x}\right)\:+\:…\:+\:\mathrm{cos}\left(\mathrm{nx}\right)\:\:=\:\:\frac{\mathrm{sin}\left(\mathrm{n}\:+\:\frac{\mathrm{1}}{\mathrm{2}}\right)\mathrm{x}}{\mathrm{2}\:\mathrm{sin}\left(\frac{\mathrm{1}}{\mathrm{2}}\right)\mathrm{x}} \\…

Question-191028

Question Number 191028 by Mingma last updated on 16/Apr/23 Answered by Frix last updated on 16/Apr/23 $$\mathrm{Not}\:\mathrm{a}\:\mathrm{proof}\:\mathrm{but}\:\mathrm{an}\:\mathrm{idea}\:\mathrm{for}\:\mathrm{a}\:\mathrm{proof}: \\ $$$$\left({n}−\mathrm{1}\right){n}\left({n}+\mathrm{1}\right)×{N}={k}^{\mathrm{3}} ;\:{k}\in\mathbb{N} \\ $$$$\mathrm{We}\:\mathrm{know}\:\mathrm{that} \\ $$$$\mathrm{1}.\:\mathrm{gcd}\:\left({n}−\mathrm{1},\:{n}\right)\:=\mathrm{1} \\…

Question-191025

Question Number 191025 by Rupesh123 last updated on 16/Apr/23 Commented by Rasheed.Sindhi last updated on 17/Apr/23 $${n}=\mathrm{8} \\ $$$$\overset{×} {\mathrm{1}},\overset{×} {\mathrm{2}},\mathrm{3},\overset{×} {\mathrm{4}},\mathrm{5},\overset{×} {\mathrm{6}},\mathrm{7} \\ $$$$\:\:\:\:\left(\mathrm{1},\mathrm{2},\mathrm{4},\mathrm{6}\:{are}\:{not}\:{relatively}\:{prime}\right)…

2-3-2-2-3-2-3-2-2-3-simplify-

Question Number 59763 by ANTARES VY last updated on 14/May/19 $$\frac{\mathrm{2}+\sqrt{\mathrm{3}}}{\:\sqrt{\mathrm{2}}+\sqrt{\mathrm{2}+\sqrt{\mathrm{3}}}}+\frac{\mathrm{2}+\sqrt{\mathrm{3}}}{\:\sqrt{\mathrm{2}}−\sqrt{\mathrm{2}−\sqrt{\mathrm{3}}}} \\ $$$$\boldsymbol{\mathrm{simplify}}. \\ $$ Answered by Kunal12588 last updated on 14/May/19 $$\sqrt{\mathrm{2}+\sqrt{\mathrm{3}}}=\sqrt{\frac{\mathrm{4}+\mathrm{2}\sqrt{\mathrm{3}}}{\mathrm{2}}} \\ $$$$\sqrt{\mathrm{2}+\sqrt{\mathrm{3}}}=\frac{\mathrm{1}+\sqrt{\mathrm{3}}}{\:\sqrt{\mathrm{2}}}…

f-x-f-x-x-f-5-1-f-1-

Question Number 190618 by mustafazaheen last updated on 07/Apr/23 $$\mathrm{f}\left(\mathrm{x}−\mathrm{f}\left(\mathrm{x}\right)\right)=\mathrm{x}\:\:,\mathrm{f}\left(\mathrm{5}\right)=−\mathrm{1} \\ $$$$\mathrm{f}\left(−\mathrm{1}\right)=? \\ $$ Answered by aba last updated on 07/Apr/23 $$\mathrm{f}\left(\mathrm{5}−\mathrm{f}\left(\mathrm{5}\right)\right)=\mathrm{5}\Rightarrow\:\mathrm{f}\left(\mathrm{4}\right)=\mathrm{5} \\ $$$$\mathrm{f}\left(\mathrm{4}−\mathrm{f}\left(\mathrm{4}\right)\right)=\mathrm{4}\Rightarrow\mathrm{f}\left(−\mathrm{1}\right)=\mathrm{4} \\…