sin(π/4 + x) + sin(π-x) = √2 cosx
2007-11-30 02:11:13 · 3 answers · asked by Princess 2 in Science & Mathematics ➔ Mathematics
sin(π/4 + x) + sin(π/4-x) = √2 cosx
2007-11-30 03:13:14 · update #1
sin(π/4 + x) + sin(π/4 - x) = √2 cosx
L.H.S. = sin(π/4 + x) + sin(π/4 - x)
= sin π/4 cos x + cos π/4 sin x + sin π/4 cos x - cos π/4 sin x
= 2 sin π/4 cos x
= 2(1/√2) cos x
= √2 cos x = R.H.S.
2007-11-30 04:35:18 · answer #1 · answered by bharat m 3 · 1⤊ 0⤋
This is not true.
If x = 0, then sin(Ï/4 + x) + sin(Ï-x) = sin(Ï/4) + sin(Ï) = â2/2 + 0 = â2/2
and
â2 cosx = â2 cos(0) = â2 * 1 = â2
Correct the statement and add details.
2007-11-30 10:21:57 · answer #2 · answered by Steiner 7 · 0⤊ 0⤋
sin(Ï/4 + x) + sin(Ï/4 - x) = â2 cosx
sin(Ï/4 + x) + sin(Ï/4 - x) =
= sin Ï/4 cos x + cos Ï/4 sin x + sin Ï/4 cos x - cos Ï/4 sin x
= 2 sin Ï/4 cos x
= 2(1/â2) cos x
= â2 cos x
2007-11-30 10:13:12 · answer #3 · answered by Orfeas 3 · 0⤊ 3⤋