The value of (2 cos 90) (sin 270) + (tan 180) (cot 90) is ____.
2006-10-12 14:14:34 · 14 answers · asked by Korey's Mamacita 1 in Science & Mathematics ➔ Mathematics
cos 90 = 0, and tan 180 = sin 180 / cos 180 = 0, so the value of the entire expression is 0.
2006-10-12 14:16:47 · answer #1 · answered by James L 5 · 0⤊ 0⤋
Taking all the angles are in degrees we know,
cos 90 = 0, sin 270 =0, tan 180 =0 and cot 90 = 0
Hence 0+0 =0
Thus the answer is zero.
2006-10-12 21:23:14 · answer #2 · answered by anjali 2 · 0⤊ 0⤋
2 cos 90 = 2 (0) = 0
sin 270 = - sin 90 = -1
tan 180 = sin 180 / cos 180 = sin 0 / - cos 0 = 0/-1 = 0
cot 90 = cos 90 / sin 90 = 0/1 = 0
(2 cos 90)(sin 270) + (tan 180)(cot 90)
= (0)( -1) + (0)(0)
= 0. final answer
the trick is to remember that:
1) sin x always refers to the vertical y-axis
2) cos x always refers to the horizontal x-axis
3) tanx = sinx/cosx
4) cotx = cosx/sinx
5) know where the radius is and its +/- components for a given angle. Drawing the cartesian plane helps.
2006-10-12 21:33:05 · answer #3 · answered by naike_10021980 2 · 0⤊ 0⤋
Since, cos 90 = 0 & Tan 180 = 0,
therefore, the value must be 0
2006-10-12 21:52:02 · answer #4 · answered by Anonymous · 0⤊ 0⤋
0
2006-10-12 21:17:22 · answer #5 · answered by raj 7 · 0⤊ 0⤋
(2 cos 90) (sin 270) + (tan 180) (cot 90)
cos 90=0
sin 270=-1
tan180=0
cot 90=cos90/sin 90=0/1=0 so
2*0*(-1)+0*0=0
2006-10-12 21:31:51 · answer #6 · answered by yupchagee 7 · 0⤊ 0⤋
It's "0".
2006-10-12 21:31:25 · answer #7 · answered by ViCKi!™|` 5 · 0⤊ 0⤋
ZERO... because:
cos90 = 0
tan 180 = 0
2006-10-12 21:18:06 · answer #8 · answered by Adriana 5 · 0⤊ 0⤋
0 !
2006-10-12 21:36:24 · answer #9 · answered by Freesia 5 · 0⤊ 0⤋
the answer is 0
2006-10-12 21:18:27 · answer #10 · answered by Mark Antony 3 · 0⤊ 0⤋