9^2 • 9^6 = 9^(2 + 6) = 9^8
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
Answer:
5 inches
Step-by-step explanation:
Area of the cake:
- 1 slice = 13 in²
- 6 slices = 13 in² * 6 = 78 in²
Area circle: πr²
Solve for r:
-Chetan K
