Anyone know how to do these questions?

Question

Find the domain and range for each function
a.) y=Sqr (x-4)

b.) y=Sqr (x^2-4)

c.) y=Sqr (4-x^2)

determine the points of intersect:

y=cos(x) and y=sin (x) in the first quadran

Answer 1

a.) y=Sqr (x-4)
Domain is x >= 4. [Otherwise y is imaginary]
Range is y =/> 0

b.) y=Sqr (x^2-4)
Domain is x =/>2 and x =/<-2
Range is y =/> 0

c.) y=Sqr (4-x^2)
Domain is |xI =/< 2
Range is 0 =/< y =/< 2

determine the points of intersect:

y=cos(x) and y=sin (x) in the first quadran
cosx=sinx --> sinx/cos x = tanx = 1 so x = pi/4 = 45 degrees.

Answer 2

wut?