Prove the following identi
v 1-cos2A/sin2A=tanA

 1-cos2A/sin2A

=(1-cos^2 A+sin^2 A)/(2sinAcosA)

=(sin^2 A+sin^2A)/2sinAcosA

=2sin^2 A/2sinAcos^2 A

=sinA/cosA

=tanA

0.16 or 16%

step-by-step explanation:

lets take a coin for example.

if you toss it twice, it has a 1/4 chance of landing on heads both times because 1/2 * 1/2 is 1/4.

with the cards, the chance of picking dog is 0.4. having two people pick one is like picking a card twice in a row. so 0.4 * 0.4 is 0.16, or 16%