Question

no useless answers.........​

Answer 1

Answer:

sin∅ = 3/5

by squaring both sides

sin² ∅ = 9/25

we know

sin²∅ + cos²∅ = 1

cos²∅ - 1 = -sin²∅

cos²∅ - 1 = -9/25

hope this will help you

Answer 2

by property of trigonometry

sin2 + cos2 = 1

cos2 -1=sin2

cos2-1=3/5

cos2 = 3/5+1

=8/5