Answer the following questions using what youve learned from
Answer the following questions using what you\'ve learned from this unit. write your resp space provided. For questions 1 5, decide whether the equation is a trigonometric identity. Explain your reaso 1. cos2 x(1 +tan2x) 1 (3 points) 2. sec xtanx(1- sin2 x) sin x (3 points)
Solution
1. cos2x(1+ tan2x)=1
Starting with the left side
cos2x(1+tan2x)
cos2x + sin2x=1 That is the right side
2. sec x ta x (1-sin2x)=sin x
Starting with left side
We have to use the following identity
1-sin2c=cos2x
sec tanx * cos2x = (1/cos x)(sin x/cos x)*cos2x = sinx that is the right side
3. csc x(2sinx - sqrt2)=0
csc x(2sinx)- sqrt2 cos x
2- sqrt2 cos x
That is not equal to right side . So its not an identity.
