We have that
2sin²<span>x - sinx - 3 = 0
</span>
Let
A------> sin x
so
2A²-A-3=0
using a graph tool-----> to resolve the second order equation
see the attached figure
the solutions are
A=-1
A=1.5------> is not solution because sin x <span>can not be 1.5
the solution is
A=-1
therefore
sin x=-1
x=arc sin(-1)=-90</span>°
the answer is
sin x=-1x=-90° or 270°
The decision when the z value is within the rejection region is that we'll have to reject the null hypothesis.
<h3>What is a rejection region?</h3>
It should be noted that the rejection region is also known as the critical region. It is the set of values where the null hypothesis is rejected.
When the observed test statistic is in the rejection region, we'll have to reject the null hypothesis and then accept rte alternative hypothesis.
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cos A is 0.8511 and tan B is 1.6
Step-by-step explanation:
Find the 3rd length or the hypotenuse.
<u>Pythagoras theorem</u>
=
+ 
=
+ 
= 64 + 25
hypotenuse = 
hypotenuse = 9.4
a) Cos A
<u>Data:</u>
Adjacent = 8
Hypotenuse = 9.4
<u>Formula:</u>
Cos (Angle) = 
Cos A = 
Cos A = 0.8511
A =
(0.8511)
A = 31.7°
b) Tan B
<u>Data: </u>
Opposite = 8
Adjacent = 5
<u>Formula:</u>
Tan (Angle) = 
Tan B = 
Tan B = 1.6
B =
(1.6)
B = 58°
Therefore, cos A is 0.8511 and tan B is 1.6.
Keyword: cos, tan
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This is a formula chart to help(i would’ve given you the answer but you didn’t give the sharp)
X = 15
Add 5 to each side
10 + 5 = 15