sin2+cos2 what is answer

Answer 1

The real answer you probably want is towards the bottom of this post. But given the way it's written, you might want look at a couple other possibilities. Still it's hard to go wrong with saying the answer is one.

use a calculator with a trig function

sin2 = 0.0349

cos2 = 0.9994

sin2 + cos2 = 0.0349 + 0.9994 = 1.0343

slightly more than 1, or round off to 1.0 for one decimal place.

sin0 + cos0 = exactly 1

the closer x is to 0, or 180, the closer sinx+cosx is to 1

and the closer x is to 90 or 270, the closer sinx+cosx is to 1 or -1.

UNLESS you meant 2 radians

then sin(2 radians) + cos(2 radians) =

sin2(57.296) + cos2(57.296) =

sin114.592 + cos114.592 = .909-.416 = .493

but generally, if radians are meant, the number has a pi in it. 1 radian though is 180/pi = about 57.296

if 0<x<90 then

1 < sinx + cosx < sqr2

1 < sinx + cosx < 1.4142

the closer x is to 45 degrees, the closer sinx+cosx = sqr2

sin^2(x) + cos^2(x) may be what you really meant to write.

then it = exactly 1.

It's like the graph of a circle with radius 1 and center at the origin, or the Pythagorean Theorem. x^2 + y^2 = r^2 = 1^2 = 1

(sine of x) squared plus (cosine of x) squared always equals one. It's a trig identity, true regardless of the value of the angle.