Grade 99 grade maths
- sin 21 cos 9 – cos 84 cos 6
- cos 66 + sin 84 in degrees
- sin 21 cos 9 – cos 84 cos 6
- cos 66 + sin 84 in degrees
1 Answer
PRANAV KUMAR
Multiplying it by 2 ,
=2sin21°cos9° – 2cos84°cos6°
=cos(21–9)°– cos(21+9)° – cos (84+6) –cos(84–6)
=cos 12° – cos30° – cos90° – cos78°
=cos(90–78)°–√3/2 – 0 – cos 78°
=sin78° –0.87–cos 78°
=0.97–0.87– 0.20
=–0.1
=2sin21°cos9° – 2cos84°cos6°
=cos(21–9)°– cos(21+9)° – cos (84+6) –cos(84–6)
=cos 12° – cos30° – cos90° – cos78°
=cos(90–78)°–√3/2 – 0 – cos 78°
=sin78° –0.87–cos 78°
=0.97–0.87– 0.20
=–0.1
Other Related Questions on 9 grade maths
What are the differences between similar triangles and congruent triangles?
What are the differences between similar triangles and congruent triangles?
9 grade maths
Last Activity: 1 Year ago
The L.C.M of the smallest 2 digit composite number and the smallest composite number is:
- (a) 12
- (b) 4
- (c) 20
- (d) 44
The L.C.M of the smallest 2 digit composite number and the smallest composite number is:
- (a) 12
- (b) 4
- (c) 20
- (d) 44
9 grade maths
Last Activity: 1 Year ago