Looking for HSC notes and resources? Check out our Notes & Resources page

Trig Question (1 Viewer)

Thread starter rand_althor
Start date Jun 6, 2015

R

rand_althor

Active Member

#1

Hey could someone please help me show the following?

$\text{Show that if } 0<x<\frac{\pi}{4}\text{, then } \sin{(2x)}>2\sin^2{(x)}.$

Thanks!

I

InteGrand

Well-Known Member

#2

rand_althor said:
Hey could someone please help me show the following?

$\text{Show that if } 0<x<\frac{\pi}{4}\text{, then } \sin{(2x)}>2\sin^2{(x)}.$

Thanks!

$$\sin 2x = 2\sin x \cos x > 2 \sin^2 x$, because $\cos x > \sin x$ for $0<x<\frac{\pi}{4}$ (check a graph to see this).$

R

rand_althor

Active Member

#3

Thanks for the help!

B

braintic

Well-Known Member

#4

OR

2sinxcosx/2sin^2(x) = cotx >1 for given domain

sin2x > 2sin^2(x)

You must log in or register to reply here.

Share:

Facebook Twitter Reddit Pinterest Tumblr WhatsApp Email Link

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top