Find the derivative of the function using the derivative rule y = cos3x * ln (2x-3).
Using basic differentiation formulas and differentiation rules:
(x ^ n) ‘= n * x ^ (n-1).
(sin (x)) ‘= cos (x).
(cos (x) ‘= -sin (x).
(c * u) ’= c * u’, where c is const.
(u ± v) ‘= u’ ± v ‘.
(u / v) ’= (u’v – uv’) / v ^ 2
y = f (g (x)), y ‘= f’u (u) * g’x (x), where u = g (x).
Thus, the derivative of our given function will look like this:
f (x) ‘= (cos (x) / (3x ^ 2 + 4))’ = ((cos (x)) ‘* (3x ^ 2 + 4) – (cos (x) * (3x ^ 2 + 4) ‘) / (3x ^ 2 + 4) ^ 2 = ((cos (x))’ * (3x ^ 2 + 4) – (cos (x) * ((3x ^ 2) ‘+ (4)’ )) / (3x ^ 2 + 4) ^ 2 = (-sin (x) * (3x ^ 2 + 4) – (cos (x) * (6x + 0)) / (3x ^ 2 + 4) ^ 2 = (-sin (x) * (3x ^ 2 + 4) – 6x * (cos (x)) / (3x ^ 2 + 4) ^ 2.
Answer: The derivative of our given function will be equal to f (x) ‘= (-sin (x) * (3x ^ 2 + 4) – 6x * (cos (x)) / (3x ^ 2 + 4) ^ 2.