Why is this multiplication wrong?

Question

f(t) = sint(1+t) 

so for values of sin 

sin(0) :  0(1+0) = 0 that is correct according to my excersise

sin(pi/3) : sqrt3/2 (1+pi/3) = sqrt3/2(1+pi/3) = 2.047198 wrong according to my book should be 1.2853 

sin(pi/6) : 1/2(1+pi/6) = 0.762 wrong book says it should be 1.3603

sin(pi/2): 1(1 + pi/2) = 2.57 this one is correct

ive tried 

sin 2pi/3 wrong

sin 5pi/6  wrong

 

im confused. 

Answer 1

Hi Rick, here are the answers I got:

 

f(π/6) = 0.762 (agrees with you)

f(π⁄3) = 1.773 (disagrees with both you and the book)

f(2π/3) = 2.680

f(5π/6) = 1.809

 

If your interpretation of the function is correct, then your answer for pi/6 should definitely be right.

Answer 2

sin(pi/3) : sqrt3/2 (1+pi/3) = sqrt3/2(1+pi/3) = 2.047198 wrong according to my book should be 1.2853

 

f(t) = sint(1+t)   ????  

 

This is one of the most confused questions that I have ever seen presented!