Is f^ supposed to be the first derivative if f?
Is the f(x) function sin^3(x) or sin(3x) ?
f(x)=sin3x, find f^(79) and f^(120)?
What am I suppose to do?
3 answers
it is f(x)= sin(3x) and yes it is suppose to be the derivative
y = sin t
dy/dx = dt/dx cos t
so if
y = sin 3x
dy/dx = d/dx(3 x) cos 3 x
= 3 cos 3x
so if x = 79 for example
dy/dx = 3 cos 3*79 = 3 cos 237
by the way I am surprised that it is in fact not
y = sin^3 x
in which case you would get
dy/dx = 3 sin^2x cos x
dy/dx = dt/dx cos t
so if
y = sin 3x
dy/dx = d/dx(3 x) cos 3 x
= 3 cos 3x
so if x = 79 for example
dy/dx = 3 cos 3*79 = 3 cos 237
by the way I am surprised that it is in fact not
y = sin^3 x
in which case you would get
dy/dx = 3 sin^2x cos x
1 answer