Wednesday

July 30, 2014

July 30, 2014

Posted by **Hello** on Friday, March 11, 2011 at 10:32am.

y=2sinxcosx

- Calculus -
**Reiny**, Friday, March 11, 2011 at 10:42amto ways to do it

1. recognize that 2sinxcosx = sin(2x)

then dy/dx = 2cos(2x)

or

2. y = 2sinxcosx

dy/dx = 2sinx(-sinx) + 2cosx(cosx)

= 2(cos^2x - sin^2x)

which just happens to be 2cos(2x) as above

**Related Questions**

Calculus grade 12 - a) determine the derivative of y = sin2x b) determine the ...

math - solve algebraically, express the roots in exact form 2sinxcosx-1=0 I got...

Calculus - Solve identity, (1-sin2x)/cos2x = cos2x/(1+sin2x) I tried starting ...

Calculus--> bobpursley - How do you get m=0? from taking the second ...

math - Prove the identity: 1-cos2x/sin2x = 1+tanx/1+cotx I simplified the RS to ...

trig - Solve for [0, 360) 2sinxcosx + cosx =0 2sinxcosx = -cosx 2sinx = -cosx/...

calculus - Find the exact values of x if 0<=x<=pi and 2sin^2(x)-sinx-...

Calculus - derivatives - Okay, I want to find the derivative of (x^x)^(x^x)... ...

Calculus II - How does one obtain cos2x = cos^2(x) - sin^2(x) by differentiating...

mathh - this is for proving identies and its fustrating i can't solve this one ...