2007-05-16 17:52:36 · 4 answers · asked by radell10 2 in Science & Mathematics ➔ Mathematics
cos(A-B) = cosAcosB + sinAsinB
cosA = sqrt(1 - sin^2 A)
cosB = sqrt(1 - sin^2 B)
You can figure out the rest.
4*[1 + sqrt(165)] / 63
2007-05-16 18:04:55 · answer #1 · answered by Dr D 7 · 1⤊ 0⤋
= cos A.cos B + sin A.sin B
= â33/7.â80/9 + 4/7.1/9
= â2640 / 63 + 4 / 63
= (1/63).(â2640 + 4)
=(1/63)(4â65 + 4)
= (4 /63).(â65 + 1)
2007-05-17 08:59:16 · answer #2 · answered by Como 7 · 0⤊ 0⤋
frist formula of
cos(A-B)=cosAcosB+sinAsinB
given
sinA=4/7
and
sinB=1/9
cosA=root33/7
cosB=4root5/9
so the answer is
(4+4root165)/63
2007-05-17 01:28:13 · answer #3 · answered by ♫●GARV●♫ 6 · 0⤊ 0⤋
cos(A-B)=cosAcosB+sinAsinB
sinA=4/7 sinB=1/9
cosA=root33/7
cosB=4root5/9
ans=(4+4root165)/63
2007-05-17 01:09:33 · answer #4 · answered by Naveen 2 · 0⤊ 0⤋