So lets get to the problem
<span>165°= 135° +30° </span>
<span>To make it easier I'm going to write the same thing like this </span>
<span>165°= 90° + 45°+30° </span>
<span>Sin165° </span>
<span>= Sin ( 90° + 45°+30° ) </span>
<span>= Cos( 45°+30° )..... (∵ Sin(90 + θ)=cosθ </span>
<span>= Cos45°Cos30° - Sin45°Sin30° </span>
<span>Cos165° </span>
<span>= Cos ( 90° + 45°+30° ) </span>
<span>= -Sin( 45°+30° )..... (∵Cos(90 + θ)=-Sinθ </span>
<span>= Sin45°Cos30° + Cos45°Sin30° </span>
<span>Tan165° </span>
<span>= Tan ( 90° + 45°+30° ) </span>
<span>= -Cot( 45°+30° )..... (∵Cot(90 + θ)=-Tanθ </span>
<span>= -1/tan(45°+30°) </span>
<span>= -[1-tan45°.Tan30°]/[tan45°+Tan30°] </span>
<span>Substitute the above values with the following... These should be memorized </span>
<span>Sin 30° = 1/2 </span>
<span>Cos 30° =[Sqrt(3)]/2 </span>
<span>Tan 30° = 1/[Sqrt(3)] </span>
<span>Sin45°=Cos45°=1/[Sqrt(2)] </span>
<span>Tan 45° = 1</span>
A graph shows the appropriate choice to be
A. 277.8 °F
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Of course, you get the same result by evaluating
76 + 301*e^(-0.40)
<span>Hence
2L + C = 1.4
-2L - 6C = -3.4
Add (This will eliminate 'L' )
-5C = -2.0
5C = 2.0
C = 0.4 = £0.40p
2L + 0.4 = 1.40
2L = 1.40 - 0.40 = 1.00
L = 0.50 = £0.50p.
Hence a lemonade (L) costs £0.50p & a Crisps (C) costs £0.40p.</span>
To find the unit price we need to divide the amount of money the item cost by the amount of items we have. Lets do it:-
35.34 ÷ 6 = <span>5.89
1 pair of socks cost $5.89.
CHECK OUR WORK:-
5.89 </span>× 6 = <span>35.34.
We were RIGHT!!
So, 1 pair of socks costs $5.89.
Hope I helped ya!! </span>
