Question

sinA=24/25 where A∈2nd axis then find the value of sinA.cosA .

Answer 1

Solution:-

• A ∈ 2nd Quadrant or axis.

sin = 24/25

sin²A + cos²A = 1

(24/25)² + cos²A = 1

cos²A = 1 - 576/625

cos²A = (625 - 576)/625

cos²A = 49/625

cosA = 7/25

•°• cosA = - 7/25 ....... {since it is in 2nd Quadrant}

Now,

sinA . cosA

= 24/25 × -7/25

= - 168/625 is Answer

Answer 2

Solution:-

A ∈ 2nd Quadrant or axis.

sin = 24/25

sin²A + cos²A = 1

(24/25)² + cos²A = 1

cos²A = 1 - 576/625

cos²A = (625 - 576)/625

cos²A = 49/625

cosA = 7/25

•°• cosA = - 7/25 ....... {since it is in 2nd Quadrant}

Now,

sinA . cosA

= 24/25 × -7/25

= - 168/625 is Answer