Notice that the above answers are giving you two sets of answers, both of which are correct.
f'(x) = -2*sin(tanx)*cos(tanx) * sec^2 (x)
which can also be written as
-sin(2tanx) * sec^2 (x)
2007-06-21 17:57:32
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answer #1
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answered by Dr D 7
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tan x = T
f(x) = cos^2 T
df/dt = 2 cos T DT(cost ) = - 2 cos T sin T
dt/dx = sec^ 2 x
df/dx = DT/dt*dt/dx = -2 cos t sin t sec^2 x
= - 2 cos (tan x) sin (tan x) sec^2 x
2007-06-21 17:50:44
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answer #2
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answered by Anonymous
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a. first, remedy for y: y=(one hundred-x^2)^(a million/2) then exchange something for the one hundred-x^2=U: y=U^(a million/2) then derivatize that: .5du*U^(-a million/2) and the one hundred-x^2: -2x=dU then placed U and dU interior the equation: dy/dx=.5(-2x)(one hundred-x^2)^(-a million/2) put in 6 for x and the slope is -3/4 b. even greater straightforward, derivatise the equation: dy/dx=2x put in -a million for x to get the slope: -2 and make a line with a slope of -2 that is going with the aid of -a million,a million the equation for the line is: y=-2x-a million
2016-11-07 04:34:12
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answer #3
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answered by ? 4
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let tan x = t
f(x) = cos^2 t
df/dt = 2 cos t dt(cost ) = - 2 cos t sin t
dt/dx = sec^ 2 x
df/dx = dt/dt*dt/dx = -2 cos t sin t sec^2 x
= - 2 cos (tan x) sin (tan x) sec^2 x
2007-06-21 17:27:52
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answer #4
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answered by Mein Hoon Na 7
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y = cos² (tan x)
Let u = tan x
du/dx = sec² x
y = (cos u)²
dy/du = - 2 sin u.cos u
f `(x) = dy/dx = - 2 sin (tan x).cos (tan x).sec² x
2007-06-21 19:37:22
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answer #5
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answered by Como 7
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y=f(x)
y=cos^2(tan x)
u=tan x
y=cos^2 u
dy/du = -2cos u sin u
= -sin(2u)
= -sin(2tan x)
du/dx = sec^2 (x)
dy/dx = dy/du * du/dx = -sec^2(x).sin(2tanx)
f'(x) = -sec^2(x).sin(2tanx)
2007-06-21 17:29:17
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answer #6
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answered by gudspeling 7
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Mental substitution approach:
f'(x) = 2cos(tanx)(-sin(tanx))(sec^2x) = -sin(2tanx)sec^2x
2007-06-21 17:46:31
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answer #7
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answered by sahsjing 7
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