cos(30) = sqrt(3)/2 so cosine squared is 3/4.
.3 m^2
30 degrees
180 degrees in a triangle 180-70-30 = 80 The other angle is 80 degrees
First you square root everything on both sides to cancel the squares. 30+B=78 Then subtract 30 from both sides to get B=48. So the answer is B=48
Each side of the triangle is 45cm/3=15cm. The altitude divides the base into two equal segments of 7.5cm. This results in a right triangle with hypotenuse 15 cm and base 7.5cm. Pythagorus tells us a2+b2=c2 where a=altitude, b=base, c=hypotenuse. a2=c2-b2=152-7.52=225-56.25=168.75, a=12.99cm. Alternatively, the 3 angles of an equilateral triangle are all 60 degrees. The altitude divides one of these angles into two 30 degree angles. The cosine of 30 degrees is the opposite divided by the adjacent side. The adjacent side is the altitude. Thus a/c=cosine of 30 degrees, a=c X cos30 degrees = 15X0.866=12.99cm
You cannot. The cosine of 30 degrees is an irrational number.
0.866 ( or (sqrt 3)/2 )
Cosine(30) = sqrt(3)/2
cos(30 deg) = sqrt(3)/2 = 0.8660 approx.
If you know the angle's sine, cosine, or tangent, enter it into the calculator and press <inverse> sine, cosine, or tangent. On MS Calc, in Scientific Mode, using Degrees, enter 0.5, then check Inv and the press sin. You should get 30 degrees. The other functions work similarly.
0.15425145
You would use trigonometry for that. If, for example, you have a force of magnitude 10 at an angle of 30 degrees: * The x-component is 10 times the cosine of 30 degrees * The y-component is 10 times the sine of 30 degrees Or better yet, learn to use the polar-->rectangular conversion on your scientific calculator.
If its a 300-600-right angle triangle then the third angle must be 90 degrees. Then its base squared plus its height squared equals its hypotenuse squared usually written in the form of: a2+b2 = c2
mostly it comes from memorization. If sin 30 = 1/2, then arcsin (1/2) = 30
The length of the other two sides is 7 cosine (60) and 7 cosine (30)that is 3.5 and 6.062 cmthe perimeter = 7 + 3.5 + 6.062 = 16.562 cm
area = 225 pi = pi R squared/4 R = square root 900 = 30 in
5.477225575 squared equals 30.