>> % Question 1
>> q1a = 123/456

q1a =

    0.2697

>> q1b = log(5)

q1b =

    1.6094

>> q1c = log10(5)

q1c =

    0.6990

>> q1d = tan(6)

q1d =

   -0.2910

>> q1e = 71/3

q1e =

   23.6667

>> q1f = exp(8)

q1f =

   2.9810e+03

>> q1g = sin((2*pi)/3)

q1g =

    0.8660

>> q1h = sin(cos(9))

q1h =

   -0.7902

>> q1i = exp(2*sqrt(3*sin(4+log10(5))+6)-7)+8

q1i =

    8.0291

>> % Question 2
>> r = 6; A=pi*r^2

A =

  113.0973

>> % Question 3
>> help acos
 acos   Inverse cosine, result in radians.
    acos(X) is the arccosine of the elements of X. Complex
    results are obtained if ABS(x) > 1.0 for some element.
 
    See also cos, acosd.

    Documentation for acos
    Other uses of acos

>> a=1/2; acos(a)/pi

ans =

    0.3333