please help...?

Question

1. What is the tangent of 45º? I think its 1 but I am unsure!



2. What is the value of sin 45º?
A.
sqrt2 / 2

B.
sqrt3 / 2

C.
sqrt2

D.
sqrt3

A little confused on how to do this one! I know how to find sin 45 degrees but none of the answers seem to be working out and these are the only possible answers!?



3. An isosceles right triangle that has a hypotenuse of length 14.14 cm has legs that are ______ cm long. Round your answer to the nearest whole cm.

Answer 1

tan 45° =

π/4 radians

value = 1

- - - - - - - - -

sin 45° =

Value = √2 / 2

- - - - - - - - -s-

Answer 2

Imagine that you have an isoceles right triangle. That means the triangle has 1 right angle and 2 45 degree angles.

The side opposite the right angle is the hypotenuse and the sides opposite the 45 degree angles are the same.

Suppose the sides opposite the 45 degree angles are 1 each. By the pythagorean theorem, the square of the hypotenuse is 1^2 + 1^2 = 2 so the hypotenuse is sqrt(2).

The sine of the 45 degree angle is the length of the opposite side divided by the length of the hypotenuse.

sin (45 degrees) = 1 /sqrt(2) = sqrt(2)/2 which is choice A.

The cosine of the 45 degree angle is the length of the adjacent side (which is the same as the opposite) divided by the length of the hypotenuse

cos (45 degrees) = 1/sqrt(2) = sqrt(2)/2

tan (45 degrees) = sin (45 degrees) / cos (45 degrees) = 1

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For 3 it helps to know that sqrt(2)=1.414... and therefore 10sqrt(2)=14.14...

So now instead of our triangle having sides of 1,1,sqrt(2) we have a,a,10sqrt(2)

a^2+a^2=100*2

2a^2=200

a^2=100

a=10

Answer 3

first: put two triangles in your memory bank
equalateral with sides 2. Draw line from corner to base. That splits base. Triangle there has sides 1, Sqrt(3) and 2 hypot. Angles are 30, 60, 90. read all trig functions.
2nd triangle: right triangle sides 1. Hyp. = Sqrt(2) => tan45=1, sin45=1/swrt(2) etc.
note 1/sqrt(2)=Sqrt(2)/2 so A. is answer. 3!

Answer 4

1.tan 45 is 1
n sin 45 would b sqrt.2/2

thrs a smal trick for findin the value of sin which i think can help u a lott ...

To find the value of --Sin 0degrees ---divide 0/4=0
Sin 30 degrees---divide 1/4=1/2
sin 45 degrees----divide 2/4=1/sqrt2 which is also equal to sqrt 2/2
Sin 60degrees -----divide 3/4=sqrt3/2
Sin 90 degrees-----divide 4/4=1

I hope this helps u out ...!!

Answer 5

tan 45 degrees =1
sin 45 degrees =1/sqrt2
9.998cm long

Answer 6

1.You are right.It is 1
2.1/sqrt2 .It is equal to sqrt2/2
3.The other sides are equal
Let it be x cm each
Hence x^2+x^2=14.14^2
=>2x^2=200cm^2
=>x^2=100cm^2
x=10 cm
Each side will be 10 cm

Answer 7

see if going to this website helps.
http://www.math.colostate.edu/dept/IMP/SG/MPE_Review/trigonometry.html