Question

4^2 - 4sin^2(x) = 4cos^2


true or false?

Answer 1

sin^2+cos^2=1 if i remember correctly

Answer 2

yep

Answer 3

so all you have to do is test by moving the equations over.

Answer 4

4^2 - 4sin^2(x) = 4cos^2(x)
4(2 - sin^2(x)) = 4(cos^2(x))
2 - sin^2(x) = cos^2(x)
sin^2(x) + cos^2(x) = 2

^^ This is not true, therefore the equation you have is false.

Answer 5

4 - 4sin^2(x) = 4cos^2 How about this ? True or false ?

Answer 6

^^ That is true, because dividing the 4 from everything gets you...

\[1 - sin^2(x) = cos^2(x)\]
Which simplifies to...

\[sin^2(x) + cos^2(x) = 1\]
^^ This is correct, therefore the equation you have is true.