If we estimate sin01 as 01 use trigonometric identities to e

If we estimate sin(0.1) as 0.1, use trigonometric identities to estimate cos(0.1), sin(0.2), cos(0.2), and sin(0.3). Compare these approximations with what you get using a calculator (using radians).

Solution

cos(0.1) = 1 - sin^2(0.1) = 0.99

sin(0.2) = 2*sin(0.1)*cos(0.1) = 2*0.1*0.99 = 0.198

cos(0.2) = 1 - sin^2(0.2) = 0.960796

sin(0.3) = 3sin(0.1) - 4sin^3(0.1) = 3*0.1 - 4*0.001 = 0.296