solve cos2x=0.5?

1 ⤊

2007-09-07 10:03:06 · 6 answers · asked by brainless 2 in Science & Mathematics ➔ Mathematics

x = 30 degrees

Approach:
Take inverse cosine of both sides: 2x = 60 degrees

2007-09-07 10:08:37 · answer #1 · answered by K N 123 3 · 1⤊ 0⤋

2x = 60°, 420° , 300° , 660°
x = 30° , 210° , 150° , 330°

2007-09-07 11:09:42 · answer #2 · answered by Como 7 · 0⤊ 0⤋

Cos 2x 0.5

2016-12-14 12:16:47 · answer #3 · answered by ? 4 · 0⤊ 0⤋

2x = cosINV (1/2)
2x = 60 degrees ( or pi/3)
x = 30 degrees ( or pi/6)

2007-09-07 13:33:06 · answer #4 · answered by james w 5 · 0⤊ 0⤋

if y=2x
cosy=0.5
cos^-1(0.5)=60
therefore y=60
60=2x
60/2=x
x=30

2007-09-07 10:11:11 · answer #5 · answered by eazylee369 4 · 0⤊ 0⤋

.25 duh

2007-09-07 10:10:23 · answer #6 · answered by rachel 2 · 0⤊ 2⤋