(a) What is the exact value of cos 510˚

The answer to your question is cos 510 = -

Step-by-step explanation:

Data

cos 510° = ?

Process

1.- Find an equivalent angle to 510° subtracting 360°

          510 - 360 = 150°

That means that if we calculate the cos 150 will be the same as cos 510

2.- Calculate the cos 150°

150° is located in the second quadrangle. In this quadrangle cosine is negative.

Also, cos 150° = 180° - 30°

If we calculate the cosine of angle 30° will be the same value of cos 150° and the same of cos 510° but with negative sign.

         cos 30° =    cos 150° =    and  cos 510° =

45

step-by-step explanation:

to find a percentage, add a decimal in front and multiply it by the other number.

.25 times 180= 45

on monday rodney ate 1/4th of the sandwich = 3/12

on tuesday he ate 1/3rd of the sandwich = 4/12

therefore in total he has eaten = 3/12 + 4/12 = 7/12

thus we can say that he has eaten 7/12 of the sandwich on monday and tuesday alltogether.

happy to

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