Why there is a difference between trignometry and matlab answers

we know that

radian ×pi/180=degree but when i calculated sin(90) that is 0.8940 and multiplied it like sin(0.8940×pi/180) give me 0.0156 not 90

[Stephen23]

"but when i calculated sin(90) that is 0.8940"

The function sin's input is in radians. What possible significance do you see in calculating sine of 90 radians ? Do you perhaps mean to calculate sine of 90 degrees ? If so, the conversion from degrees to radians is simple:

sin(valueInDegrees*pi/180)

or simpler:

sind(valueInDegrees)

"...sin(0.8940×pi/180) give me 0.0156 not 90"

Regardless of its input units, what sine function could possibly have 90 as an output value?

Answer 1

[Walter Roberson]

sin(90*pi/180)

or

sind(90)

Your current calculation is

sin(sin(90) * pi/180)

where the sin(90) is 90 radians.

[NEELPRAKASH SINHA]

sir but even i will do 0.8940×pi/180, it will also dont give 90

[Walter Roberson]

your basic formula is wrong.

degree = radian * 180/pi

[NEELPRAKASH SINHA]

ty but even with this my doubt is not cleared because it will also not lead me to the 90 degree

[Walter Roberson]

If the task is to startvwith 0.8940 and get out 90 then you are not going to be able to do that in any simple way. sin(90) means to take sine of 90 radians. sind(90) or sin(90*pi/180) would take sine of 90 degrees giving you 1.0 . asind(1.0) would give you 90.