%q1

%A
x=3/17*pi
tan(2*x)
(2*tan(x))/(1-tan(x)^2)
% 2.0083

%B
tan(x/2)
sqrt((1-cos(x))/(1+cos(x)))
% 0.2845

%q2
x=13.5

%A
x^3+5*x^2-26.7*x-52   
% 2.9592e+003

%B
sqrt(14*x^3)/exp(3*x)
%   4.7823e-016

%C
log10(abs(x^2-x^3))
%     3.3576

%3
x=5/24*pi

%A
sin(2*x)
2*sin(x)*cos(x)
% 0.9659

%B
cos(x/2)
sqrt((1+cos(x))/2)
% 0.9469

%q4
X0=2
Y0=-3
A=3, B=5, C=-6
d=abs(A*X0+B*Y0+C)/sqrt(A^2+B^2)
% 2.5725