Tuesday

September 2, 2014

September 2, 2014

Posted by **stacy** on Monday, February 27, 2012 at 12:21am.

2. If d/dx(f(3x^3))=9x^2, Calculate f'(x).

3. Let f(x)=cos(6x+6), find f'(x)

4. Let f(x)=-2sec(2x), find f'(x)

- COLLEGE CALCULUS. HELP! -
**Steve**, Monday, February 27, 2012 at 12:03pmLooks like an exercise in the chain rule:

f(x) = sin(x^2)

f'(x) = cos(x^2) * 2x = 2x cos(x^2)

f'(1) = 2cos(1)

--------------------

d/dx(f(3x^3))=9x^2

Let g(x) = f(3x^3)

dg/dx = dg/df * df/dx

9x^2 = dg/df * 9x^2

1 = dg/df

Looks like g(x) = x

so, g(f) = f

dg/dx = df/dx = 9x^2

--------------------

f(x)=cos(6x+6)

f' = -sin(6x+6)*6

= -6sin(6x+6)

----------------

f(x)=-2sec(2x)

f' = -2sec(2x)tan(2x)*2

= -2sec(2x)tan(2x)

**Answer this Question**

**Related Questions**

Calculus 12th grade (double check my work please) - 1.)Find dy/dx when y= Ln (...

COLLEGE CALCULUS. HELP! - i dont know how to start this problem. i dont like cos...

calculus - Find the points on the curve y= (cos x)/(2 + sin x) at which the ...

CALCULUS - If cos(t)=–7/9, find the values of the following trigonometric ...

Trig - Given: cos u = 3/5; 0 < u < pi/2 cos v = 5/13; 3pi/2 < v < ...

Math/Calculus - A series circuit contains a resistor with R = 24 ohms, an ...

Math - Calculus - The identity below is significant because it relates 3 ...

math - Can you please check my work. A particle is moving with the given data. ...

Calculus (help Steve plz) - 1) if w = <-8, 15>, find ||w||? 2) which ...

TRIG! - Posted by hayden on Monday, February 23, 2009 at 4:05pm. sin^6 x + cos^6...