Can you add the picture with it cuz i think you forgot
Answer:
Find sin 2x, knowing tan x = -2, and cos x > 0
Ans:
sin
2
x
=
4
5
Explanation:
3 Trig identities to be used:
1
+
tan
2
x
=
1
cos
2
x
(1)
sin
2
x
+
cos
2
x
=
1
(2)
sin
2
x
=
2
sin
x
.
cos
x
(3)
Given tan x = -2. First find cos x and sin x
(1) -->
1
+
4
=
1
cos
2
x
-->
cos
2
x
=
1
5
-->
cos
x
=
±
1
√
5
.
Since cos x > 0, then
cos
x
=
1
√
5
.
(2) -->
sin
2
x
=
1
−
cos
2
x
=
1
−
1
5
=
4
5
-->
sin
x
=
±
2
√
5
.
Since cos x > 0 then
sin
x
=
2
√
5
.
(3) -->
sin
2
x
=
2
sin
x
.
cos
x
=
2
(
1
√
5
)
(
2
√
5
)
=
4
5
Answer link
The solutions to this will be found where the graph goes through the x-axis...when y = 0. Since f(x) and "y =" are interchangeable, this makes sense. When you graph it and use your "trace" button you will find that the solutions are -1.8608, -.254102, and 2.11491
The answer is 180.
12 times 15 equals 180
18 times 10 equals 180
20 times 9 equals 180
