Why don't my iPhone calculator and graphing calculator calculate sin, cos, and tan correctly? Is there a way to fix this, and if so, how?
Maybe you need your answers given in radians instead of degrees, or degrees instead of radians?
The graphing calculator should have a setting to put it in degree mode or radian mode.
If you can't find the setting, you can convert from degrees to radians by multiplying by π / 180
( And you can convert from radians to degrees by mutiplying by 180 / π ).
What type of calculator are you using? Knowing this information will make it easier to diagnose the problem and fix it.