Question

the expression sin^2 thita =( x^2+y^2)/ 2xy is possible if
a) x=y
b) x>y
c) x=-y
d) x 12 years ago

Answer 1

\[-1\le \sin \theta \le 1\]
\[\sin ^{2} \theta \le 1\]

Answer 2

that means \[\sin^2 \le 1 \]
\[x^2 + y^2 /2xy \le 1 \]

Answer 3

\[x^2+ y^2 \le 2xy \]
then ?

Answer 4

\[x ^{2}-2xy+y ^{2}\le0\]

Answer 5

\[(x-y)^{2}\le0\]
a square quantity can not be less than zero...
so (x-y)^2=0

Answer 6

that the expression holds true if x=y right !

Answer 7

yes..

Answer 8

okei thank you very much ! @souvik

Answer 9

you are welcome..:)