Question

If 15 sin? 0 + 2 cos? 0 = 7, find the value of tan 0.​

Answer 1

2sinx+15cos

2

x=7

2sinx+15(1−sin

2

x)−7=0

2sinx−15sin

2

x+8=0

15sin

2

x−2sinx−8=0

sinx=

2.15

2±

4+4.15.8

=

30

2±

4+480

=

30

2±22

=

30

24

,

30

−20

sinx>0 (∵0<x<90

o

)

sinx=

30

24

=

5

4

cosx=

1−

25

16

=

25

9

=

5

3

tanx=

cosx

sinx

=

3/5

4/5

=

3

4

∴tanx=

3

4

.