Question

(ii) 4 sin’x + 6 cos²x = 5​

Answer 1

Answer:

cos 2∅=5-4sin∅/6

cos²∅=1-sin²∅

1-sin²∅=5-4sin∅/6

-sin²∅=5-4sin∅-5+4sin∅/6

-sin²∅=1/6

sin²∅=-1/6

Answer 2

1. 4sinX + 6 cos ^2 X = 5
2. 2(2sinX + 3cos^2X) = 5
3. 2sinX + 3cos^2 X = 5/2
4. 2sinX + 3( 1 - sin^2X) = 5/2
5. 2sinX + 3 - 3sin^2X = 5/2
6. sinX (2-3 sinX) = 5/2 -3
7. sinX(2-3 sinX) = 5-6/2
8. 2-3sinX = -sinX/2
9. 2 = -sinX/2+3sinX
10. 2 = 2sinX/2
11. 2 = sinX
12. sinX = 2 (Ans.)