Answer:
1/sqrt10
Step-by-step explanation:
1) Find out cosA using formula (cosA)^2+(sinA)^2=1
The module of cosA= sqrt (1- (-3/5)^2)= sqrt 16/25=4/5
So cosA=-4/5 or cosA=4/5.
Due to the condition 270degrees< A<360 degrees, 0<cosA<1 that's why cosA=4/5.
2) Find sinA/2 using a formula cosA= 1-2sinA/2*sinA/2 where cosA=4/5.
(sinA/2)^2= 0.1
sinA= sqrt 0.1= 1/ sqrt10 or sinA= - sqrt 0.1= -1/sqrt10
But 270°< A< 360°, then 270/2°<A/2<360/2°
135°<A/2<180°, so sinA/2 must be positive and the only correct answer is
sin A/2= 1/sqrt10
Answer:
The number which appears most often in a set of numbers.
1.98 x 10^-12 1.98
------------------ = ---------- x 10^-10
3.6 x 10^-2 3.6
=0.55 x 10^-10
=5.5 x 10^-11
Answer: y = 31 and x = 13
Step-by-step explanation: Look at the image from the top left to top right, then to bottom right to bottom left.
Answer:
<u>135.94 feet</u>
Step-by-step explanation:
Split the problem into two parts :
- Distance between viewer and building
- Height of the top part of the building
<u>Distance between viewer and building</u>
- The lower part of the building is 40 feet, as it is mentioned the viewer is 40 feet above street level
- Let the distance be called 'd'
- Therefore, tan37° = 40/d
- tan37° = 3/4 = 0.75
- ⇒ 40/d = 0.75
- ⇒ d = 40/(3/4) = 40 x 4/3 = 160/3 = 53.3 feet
<u>Height of the top part of the building</u>
- Let the height of the top part be 'h'
- Therefore, tan61° = h/d = h/53.3
- tan61° = 1.8
- ⇒ h/53.3 = 1.8
- ⇒ h = 53.3 x 1.8 = 95.94 feet
<u>Total height of building</u>
- Lower part + Top part
- 40 + 95.94
- <u>135.94 feet</u>
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