y = 2sinx/(4-3sinx)
Find dy/dx.
I keep coming to;
[(2cosx)(4-3sinx)-(2sinx)(-3cosx)]/(4-…
But evidently the answer is 8cosx/(4-3sinx)^2.
Could someone show me how one gets to that answer?
Find dy/dx.
I keep coming to;
[(2cosx)(4-3sinx)-(2sinx)(-3cosx)]/(4-…
But evidently the answer is 8cosx/(4-3sinx)^2.
Could someone show me how one gets to that answer?
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I think you got the right answer, you just didn't simplify.
Note that (2cosx)(4-3sinx)-(2sinx)(-3cosx) expands to give 8cosx
EDIT
(2cosx)(4-3sinx) = 2cos(x)*4 + 2cos(x)*-3sin(x) = 8 cos(x) - 6 sin(x) cos(x)
(2sinx)(-3cosx) = -6 cos(x) sin(x)
therefore (2cosx)(4-3sinx)-(2sinx)(-3cosx) = 8 cosx - 6 cosx sinx + 6 cosx sinx
= 8 cosx
Note that (2cosx)(4-3sinx)-(2sinx)(-3cosx) expands to give 8cosx
EDIT
(2cosx)(4-3sinx) = 2cos(x)*4 + 2cos(x)*-3sin(x) = 8 cos(x) - 6 sin(x) cos(x)
(2sinx)(-3cosx) = -6 cos(x) sin(x)
therefore (2cosx)(4-3sinx)-(2sinx)(-3cosx) = 8 cosx - 6 cosx sinx + 6 cosx sinx
= 8 cosx