I know it goes sqrt((-2)^2+(2)^2), but how does the answer 2(sqrt2) become (sqrt 2)/2 on sin and (-sqrt 2)/2 on cos. This is the answer the book gives
2007-01-28 04:33:24 · 3 answers · asked by ray10573 1 in Science & Mathematics ➔ Mathematics
In a 45 degree angle (pi/4) the both sides are 1/sqrt 2.
It is unacceptable to leave a radical in the denominator, so 1/sqrt2 is multiplied by 1 (in the form of sqrt 2 / sqrt 2)
1/sqrt 2 x (sqrt 2/sqrt 2) = sqrt 2 / 2
2007-01-28 05:10:32 · answer #1 · answered by davidosterberg1 6 · 0⤊ 0⤋
x=-2
y=2
r=â(x^2+y^2)=2â2
sinα = y/r = 2/(2â2) = â2/2
cosα = x/r = -2/(2â2) = -â2/2
2007-01-28 12:51:00 · answer #2 · answered by sahsjing 7 · 0⤊ 0⤋
r=2rt2
rcos theta=2rt2costheta=-2
cos theta=-sq.rt2/2
rsin theta=2rt2sintheta=2
sin theta=sq.rt.2/2
2007-01-28 12:37:57 · answer #3 · answered by raj 7 · 0⤊ 0⤋