I hope this is just a maths problem coz if this is your card number I wouldn't be putting it on here for all to see.
Let us start subtracting 3 cos theta both sides so that we may get all theta terms on left side only
It is now : 4 cos theta - 3 cos theta = - (sqrt3)/ 2
1 cos theta = -( sqrt 3 ) /2
we know cos (pi-x)= - cos x And cos (pi+ x)= - cos (x)
********* let us first use :
- Cos ( pi - theta) = - ( sqrt 3 )/2
this implies cos (pi- theta )= (sqrt 3) /2
cos ( pi - theta )= cos (pi /6)
pi- theta = pi/6
pi- pi/6 = theta
5 pi/6 = theta
one of teh answer is 5 pi/6 . another value of theta would be :
(2pi - 5pi/6)= 7pi/6
Answer: 5 pi/6 and 7 pi/6
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6 Find an exact value. sin 75°
</span>sin(A+B)=sin(A)cos(B)+cos(A)sin<span>(B)
</span>sin(45)=cos(45)=(2^0.5)/2 sin(30)=0.5 cos(30)=(3^0.5)/2
sin(45+30)=sin(45)cos(30)+cos(45)sin(30)=(6^0.5+2^0.5)/4
the answer is the letter d) quantity square root of six plus square root of two divided by four.
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7. Find an exact value. sine of negative eleven pi divided by twelve.
</span>sin(-11pi/12) = -sin(11pi/12) = -sin(pi - pi/12) = -sin(pi/12) = -sin( (pi/6) / 2)
= - sqrt( (1-cos(pi/6) ) / 2) = -sqrt( (1-√3/2) / 2 ) = -(√3-1) / 2√2=(√2-√6)/4
the answer is the letter c) quantity square root of two minus square root of six divided by four.
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8. Write the expression as the sine, cosine, or tangent of an angle. sin 9x cos x - cos 9x sin x
</span>
sin(A−B)=sinAcosB−cosAsinB
sin(9x−x)= sin9xcosx−cos9xsinx= sin(8x)
the answer is the letter c) sin 8x
<span>
9. Write the expression as the sine, cosine, or tangent of an angle. cos 112° cos 45° + sin 112° sin 45°</span>
cos(A−B)=cosAcosB<span>+sinA</span>sinB
cos(112−45)=cos112cos45<span>+sin112</span>sin45=cos(67)
the answer is the letter d) cos 67°
10. Rewrite with only sin x and cos x.
sin 2x - cos 2x
sin2x =
2sinxcosx<span>
cos2x = (cosx)^2 - (sinx)^2 = 2(cosx)^2 -1 = 1- 2(sinx)^2</span>
sin2x- cos2x=2sinxcosx-(1- 2(sinx)^2=2sinxcosx-1+2(sinx)^2
sin2x- cos2x=2sinxcosx-1+2(sinx)^2
<span>
the answer is the letter <span>
b) 2 sin x cos2x - 1
+ 2 sin2x</span></span>
X is a vertical angle to the angle marked as 100 degrees.
Vertical angles are the same so x = 100 degrees
Answer: 100 degrees
Answer:
D. 158.4 km²
Step-by-step explanation:
Area of sector = θ/360 * πr²
Where,
θ = 150°
r = 11 km
Substitute
Area = 150/360 * π * 11²
Area = 158.38863 ≈ 158.4 km² (nearest tenth)
