Monday

November 24, 2014

November 24, 2014

Posted by **Tim** on Sunday, March 9, 2014 at 10:40pm.

f(x) = 2 cos x + cos^2 x

at which the tangent line is horizontal. (Use n as your arbitrary integer.)

smaller y-value (x,y)=

larger y-value (x,y)=

- Calculus -
**Steve**, Monday, March 10, 2014 at 5:03amSince the derivative is the slope of the tangent line, we need

-2sinx - 2cosx*sinx = 0

-2sinx(1+cosx) = 0

sinx = 0 means x = nπ

cosx = -1 means x = (2n+1)π

so, f(x) has a horizontal tangent at x=nπ

**Answer this Question**

**Related Questions**

Calculus (Help) - The graph of y=cos x * ln cos^2x has seven horizontal tangent ...

Calculus (Help) - The graph of y=cos x * ln cos^2x has seven horizontal tangent ...

calculus - 5) Find the points on the curve below at which the tangent is ...

Calculus (Urgent Help) - The graph of y=cos x * ln cos^2x has seven horizontal ...

Calculus (Urgent Help) - The graph of y=cos x * ln cos^2x has seven horizontal ...

calculus - Find the points on the curve below at which the tangent is horizontal...

Calculus - 55. Find an equation of the tangent line to the graph of f(x) =x^3 - ...

Calculus - Given the function y=(x^2-5/x+3), answer the following questions. a) ...

maths - 1. Prove using mathematical induction that 1+2+3+...+n=[ n(n+1)]/2 2. ...

maths - 1. Prove using mathematical induction that 1+2+3+...+n=[ n(n+1)]/2 2. ...