Trig question: needs checking. Diagrams and calculations below
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length from a to b is 37.66km? and length from b to c is 2km?
What I did (all trig functions are in degrees):\[b^{2}=a^{2}+c^{2}-2ac\cos B\]\[=2^{2}+37.66^{2}-2(2)(37.66)\cos 132\]\[\approx1321.48\]
@TylerD Yes
have you tried law of sines?
I used the Cosines Law. I'm wondering if I did it right...
looks right
but did u take the square root after
im getting 39.0265km for b
wait a sec
Okay thanks. Since they want angle A, can I use the value of "segment b" that I found to do the Sine Law? :o (I lagged out sorry) yeah sorry I forgot to square root, you're right... But I got 36.35km.
now that you have an angle and the side, you can use sine law but
I calculated sqrt and got 36.___ both ways o_o; did I do something wrong
2^2+37.66^2=1422.2756 1422.2756-(2*2*37.66cos(132)) = 1523.073435 sqrt(1523.073435)=39.02657344
O_O I didn't get that at all...
I re-calculated and got 1550.0256
sin(132)/39.03 = sin(A)/2 2(sin(132))/39.03=sin(A) sin^-1(2(sin(132))/39.03)=A
OH I did addition on accident! *facepalms*
Okay, so I got 1523.07 which square roots to 39.02...
right now use law of sines.
and then I should be good for angle A?
and then solve for theta with a sin inverse
ya
Okay
Thank you ! :)
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