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The diagonal of a square is 5√2. What is the sine and cosine of the angle that it...
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You should remember that the diagonals of a square are bisectors of the angles, hence, the right triangles the diagonals form are isosceles.
Since the diagonals are the bisectors of angles, the bisected angles measure 45 degrees.
You should remember that the sine and cosine of `45^o ` have equal values.
You also should remember the definitions of sine and cosine functions such that:
`sin 45^o` = opposite leg/hypotenuse
`cos 45^o ` = adjacent leg/hypotenuse
Since the legs of triangle are also the sides of square, you should come up with the following notation for the side of square, such that:
`sin 45^o` = x/hypotenuse
`cos 45^o` = x/hypotenuse
The problem provides the length of diagonal of the square that is the hypotenuse of right triangles, also.
hypotenuse = `5sqrt2`
You need to remember that `sin 45^o = cos 45^o = sqrt2/2` such that:
`sqrt2/2 = x/(5sqrt2) =gt x = 5`
Hence, evaluating the sine and cosine of the angle that diagonal of square makes to its sides, yields `sin 45^o = cos 45^o = sqrt2/2.`
Posted by sciencesolve on June 30, 2012 at 7:19 AM (Answer #1)
first we try to get the value of the sides.
we take the diagonal to form a right triangle.
c^2 = a^2 + b^2 since a = b ( for square)
c^2 = 2a^2
(5√2)^2 = 2a^2
a = 5 and b = 5
since it is a square, we know that the angles of the sides are 90.
is it alright for you to check the question.
probably theres more into it.
but remember the sohcahtoa
sin a = 5 /(5√2 )
a = 45 degrees
cos a = 5 /(5√2 )
a = 45 degrees
Posted by jerichorayel on June 29, 2012 at 11:01 AM (Answer #3)
Now we have the properties of square as
(1) all the angles are 90
(2) all the side are equal in length
(3) The diagonals of a square bisect its angles.
So the angle would be 45
So sine 45 = 1/√2 and cos 45 = 1/√2
Posted by chaobas on June 30, 2012 at 12:36 AM (Answer #2)
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