Question

sin690cos930+tan(-765)cosec9-1170)

Answer 1

Step-by-step explanation:

sin690°cos930°+tan(−765°)csc(−1170°)

=sin(720−30)cos(900+30)+tan(−720+45)csc(3×360+90)

=(−sin30°)(−cos30°)+tan(45°)csc(90°)

=(−

2

1

)(−

2

3

)+(1)(1)

=1+

4

3

=

4

3

+4

.

Answer 2

Answer:

Step-by-step explanation:

Sin690cos930+tan(-765)cosec(-1170).

=Sin(630+60)cos(900+30) + Tan(720+45)cosec(1170+0). [tan(-x)= -tan x & cosec(-x)= -cosec x].

= (-Cos 60)(-cos 30)+tan 45 sec 0.

= (-1/2)(-√3/2) + (1 )(1).

=√3/4+ 1.

=(√3+4)/4.

Hope it helps.