What is Tan(arcsin(3/5)+arccos(5/7))tan(arcsin(35)+arccos(57))?

2 Answers

\color{red}{\tan(\sin^{-1}(3/5)+\cos^{-1}(5/7))}=\color{blue}{\frac{294+125\sqrt6}{92}}tan(sin1(35)+cos1(57))=294+125692

\approx 6.52376.5237

Explanation:

Given that

\tan(\sin^{-1}(3/5)+\cos^{-1}(5/7))tan(sin1(35)+cos1(57))

=\tan(\sin^{-1}(3/5\cdot 5/7+4/5\cdot \frac{2\sqrt6}{7}))=tan(sin1(3557+45267))

=\tan(\sin^{-1}(\frac{15+8\sqrt6}{35}))=tan(sin1(15+8635))

=\tan(\sin^{-1}(\frac{15+8\sqrt6}{35}))=tan(sin1(15+8635))

=\tan(\tan^{-1}(\frac{\frac{15+8\sqrt6}{35}}{\sqrt{1-(\frac{15+8\sqrt6}{35})^2}}))=tan⎜ ⎜ ⎜ ⎜tan1⎜ ⎜ ⎜ ⎜15+86351(15+8635)2⎟ ⎟ ⎟ ⎟⎟ ⎟ ⎟ ⎟

=\tan(\tan^{-1}(\frac{15+8\sqrt6}{\sqrt{616-240\sqrt6}}))=tan(tan1(15+866162406))

=\frac{15+8\sqrt6}{\sqrt{616-240\sqrt6}}=15+866162406

=\frac{\sqrt{180186+73500\sqrt6}}{92}=180186+73500692

=\frac{\sqrt{(294)^2+(125\sqrt6)^2+2(294)(125\sqrt6) }}{92} =(294)2+(1256)2+2(294)(1256)92

=\frac{294+125\sqrt6}{92} =294+125692

\approx 6.5237632376.523763237

Jul 11, 2018

tan(arcsin(3/5)+arccos(5/7)) = 147/46+125/92sqrt(6)tan(arcsin(35)+arccos(57))=14746+125926

Explanation:

Consider right angled triangles with sides:

3, 4, 53,4,5

5, 2sqrt(6), 75,26,7

Remember:

sin(theta) = "opposite"/"hypotenuse"sin(θ)=oppositehypotenuse

cos(theta) = "adjacent"/"hypotenuse"cos(θ)=adjacenthypotenuse

tan(theta) = "opposite"/"adjacent"tan(θ)=oppositeadjacent

Hence:

tan(arcsin(3/5)) = 3/4tan(arcsin(35))=34

tan(arccos(5/7)) = (2sqrt(6))/5tan(arccos(57))=265

Note that:

tan(alpha+beta) = (tan alpha + tan beta) / (1 - tan alpha tan beta)tan(α+β)=tanα+tanβ1tanαtanβ

So we find:

tan(arcsin(3/5)+arccos(5/7)) = tan(arctan(3/4)+arctan((2sqrt(6))/5))tan(arcsin(35)+arccos(57))=tan(arctan(34)+arctan(265))

color(white)(tan(arcsin(3/5)+arccos(5/7))) = (3/4+(2sqrt(6))/5)/(1-(3/4)((2sqrt(6))/5))tan(arcsin(35)+arccos(57))=34+2651(34)(265)

color(white)(tan(arcsin(3/5)+arccos(5/7))) = (15+8sqrt(6))/(20-6sqrt(6))tan(arcsin(35)+arccos(57))=15+862066

color(white)(tan(arcsin(3/5)+arccos(5/7))) = ((15+8sqrt(6))(10+3sqrt(6)))/((20-6sqrt(6))(10+3sqrt(6)))tan(arcsin(35)+arccos(57))=(15+86)(10+36)(2066)(10+36)

color(white)(tan(arcsin(3/5)+arccos(5/7))) = (150+45sqrt(6)+80sqrt(6)+144)/(200-108)tan(arcsin(35)+arccos(57))=150+456+806+144200108

color(white)(tan(arcsin(3/5)+arccos(5/7))) = (294+125sqrt(6))/92tan(arcsin(35)+arccos(57))=294+125692

color(white)(tan(arcsin(3/5)+arccos(5/7))) = 147/46+125/92sqrt(6)tan(arcsin(35)+arccos(57))=14746+125926