Flag Magical Mathematics[Interesting Approach]> trignometry...
question mark

If 8 sin2 A + 4 cos2 A = 5, THEN 4 sin2 A + 8 cos2 A is equal to?

Vikas TU , 13 Years ago
Grade 12th Pass
anser 1 Answers
vikas askiitian expert

Last Activity: 13 Years ago

sin2A = 1-cos2A         ............1

8sin2A + 4cos2A = 5          ..........2       (given)

putting 1 in 2

8 - 8cos2 + 4cos2A = 5

cos2A = 3/4

sin2A = 1-cos2A =  1/4

so , value of 4sin2A+8cos2A = 4(1/4) + 8(3/4)

             =7

Provide a better Answer & Earn Cool Goodies

Enter text here...
star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments


Ask a Doubt

Get your questions answered by the expert for free

Enter text here...