#1
so my problem is:

(I don't know the code for "squared" so I'll just write 2)

b2 = (20)2 + (25)2 - 2(20)(25)(Cos 48)

So I keep getting

b2 = 1025 - 1338.3

but I get a negative number, which isn't right...

help?
#2
Awww I thought you put cousin law help meaning you got in trouble for incest and I was gonna say haha inbred because you misspelled cousin damn you for having math problems damn you to hell.
Due what you want as long as you vote Due!
#5
your method seems logical, so the only thing i could think of is an imaginary solution, which doesn't seem like it would fit with the thing youre working on.... no idea
#6
Quote by tayroar
Awww I thought you put cousin law help meaning you got in trouble for incest and I was gonna say haha inbred because you misspelled cousin damn you for having math problems damn you to hell.



. <----- See that? That's called a period. You should learn how to use it.

EDIT: And I just learned the cosine law about 2 weeks ago.

Unfortunately I can't remember it.
Quote by alteredstates
If you are rowing down the road in your canoe and your wagon wheel falls off. How many pancakes does it take to make a doghouse?

Green, because a vest has no sleeves.

Can't we all just get a bong?
#7
Your value for cos 48 is wrong... cos 48 =0.669130606, 2*20*25*cos48 = 669.130606

Either your calculator was in radians or you didn't put some brackets.
#8
here's the triangle:



The answer is 18.9 cm, but I have to show how to get there.

Quote by mstysakura
Your value for cos 48 is wrong... cos 48 =0.669130606, 2*20*25*cos48 = 669.130606

Either your calculator was in radians or you didn't put some brackets.


I'm doing this: 40*50*Cos 48
Last edited by wylde_overdrive at Feb 18, 2008,
#9
Quote by mstysakura
Your value for cos 48 is wrong... cos 48 =0.669130606, 2*20*25*cos48 = 669.130606

Either your calculator was in radians or you didn't put some brackets.



Listen to him (or her)
#10
Quote by wylde_overdrive
here's the triangle:



The answer is 18.9 cm, but I have to show how to get there.


I'm doing this: 40*50*Cos 48


i though if you had 2 sides and the included angle it was 1/2 x side a x side b x cos included but i could be wrong


edit: nevermind, i think thats wrong, but i'll check
#12
Looks like your calculator is measuring in radians. Make sure mode is in degrees. So hit mode button until the little thing at the top says "deg" and not "rad".
#13
Quote by apope
Looks like your calculator is measuring in radians. Make sure mode is in degrees. So hit mode button until the little thing at the top says "deg" and not "rad".


It is measuring in degrees.
#14
Wait.. if it's negative don't you type in the negative number, then 2nd cos (on the calculator)?
#15
Quote by Jaron Gao
theres nothing wrong with the information

just use the consine law rule, set your calculator to degrees

you should have

b^2=(25^2)+(20^2)-2(25)(20)cos(48)

and it equals

18.86cm

its all correct


How do I do the last part? is it 40 * 50 * 2x cos 48?
#16
just distribute the 2x25 and be done.... no more distributing, its like the 2 was in its own parenthesis isnt it? (2)(25)(20)(cos48)