A bit of help please if possible :D (1 Viewer)

[MilkDrinker]

Hi guys, just preparing for my maths 3U test on Friday and came across some questions I didn't quite get.
Could you please advise me on how I would go about answering {exact value} :



btw the answer is 4/5 but I don't know the process of getting to that answer

Thanks

 

[petermik]

Good question. Lol I got mine on friday too fml, well it is possible for just inputting 2 times inverse tan of 1/2 in your calculator then finding the sine of that finding 0.8 simply 4/5. The preferred method , it is obvious that 2tan inverse 1/2 (sorry I forgot how to use latex lol) is an angle, say theta. There fore it is Sin 2(theta), use the identity 2Sin(theta)cos(theta) .. and there you go remember to use the triangle, opposite is 1 adjacent is 2 hypotenuse is root 5 then you just go 2 x 1/root5 x 2/root 5

 

[MilkDrinker]

SOOOOO SMART!!!
I forgot about that method....
Thanks sooo much...
for your help, I shall remind of how to use LaTeX.
type [.tex] before what you want and [./tex] after what you want (without the full stops)
well, that's what I got taught anywyay...
Thanks so much
cya