Question

if Tan(theta)=x, then Sin(2*theta) is equal to:

the possible answers are:

a) 2x
b) 1+x^2
c) (1+x^2)/2
d) (2x)/(1+x^2)

Please help

Answer 1

possible answer "c" is wrong. The correct answer is "(1+x^2)/2x"

Answer 2

you need to use
\[\sin(2x)=2\sin(x)\cos(x)\]

Answer 3

Ok let me try

Answer 4

you need of course to find
\[\sin(x)\] and \[\cos(x)\]

Answer 5

I got a really weird thing. This is what I did.

sen(2theta)=2sin(theta)cos(theta)
Tan(theta)=sen(thetha)/Cos(theta)
sen(theta)=xCos(theta)

sen(2theta)=2XCos(theta)Cos(theta)
sen(2theta)=2XCos2(theta)

Answer 6

Im really bad at this. can you show the work

Answer 7

draw a triangle and convince yourself that if
\[tan(\theta)=x\] then
\[\sin(\theta)=\frac{x}{\sqrt{1+x^2}}\] and
\[\cos(\theta)=\frac{1}{\sqrt{1+x^2}}\]

Answer 8

ahhh by pythagoras. Clear.

Answer 9

Should I Apply sen(2thta)=2Sin(theta)Cos(theta)? I think so

Answer 10

Satellite can you help me with the question I just posted, please?

Answer 11

This question in already solved. I need help in my lattest question

Answer 12

ya you can apply 2 sin thta * cos thta.............but it takes too much time....just apply sin(2tha)= (2tan tha)/(1 + tan^2 thta)...
if you apply this than your answer becomes (d)

Answer 13

the answer is d as in deliciousness