If 3 sin A + 4 cos A = 5, then 4 sin A - 3 cos A is
equal to
(1) O
(2) 1
(3) 2
(4) 3
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3SinA +4CosA =5
Divide by 5 to all
3/5 SinA+4/5 cosA =1
If 3/5=cosA then 4/5 = sinA
Ie cosA sinA + sinA cosA =1
Sin2A=1
2A =90
A=45
Therefore 4sinA -3cosA
= 4sinA -3cosA
= 4sin45 -3cos45
1/square root 2
Divide by 5 to all
3/5 SinA+4/5 cosA =1
If 3/5=cosA then 4/5 = sinA
Ie cosA sinA + sinA cosA =1
Sin2A=1
2A =90
A=45
Therefore 4sinA -3cosA
= 4sinA -3cosA
= 4sin45 -3cos45
1/square root 2
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