Solve log2(x) = 4.5, accurate to two decimal places.

If sin y = 7/q and tan y= 7/r then the value of cos y is

Solution:

The values of sin y and tan y are given as 7/q and 7/r respectively.

We know the relationship between tan cos and sin which is

 --- equation 1

Since we already know the values of sin y and tan y we can easily find the value of cos y by substituting the values in eq1

Taking cos y to the other side of the equal to sign we get

Hence the value of cos y is