still having some calculus problems...?

Question

f (x) = sqrt of 1+x
g(x) = sqrt of 1-x

domain of f+g, domain of f-g, domain of fg
domain of f/g
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NEXT

I know an inverse will "undo" what the function does but I don't think i'm doing these correctly:

f(x)= 6x+2
f^-1(x)=?

g(x)= 13x^3 - 7
g^-1(x)=?

h(x)= 6/x+7
h^-1(x)=?

j(x)= cubic rt of x+13
j^-1(x)=?
I know that this is the same as y^1/3
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LAST Question!

using the Cartesian equation (y=mx+b)
what is m and b?

I eliminated the parameter of t and solved for t in terms of x and substituted into the equation for y, then tried to get m and b from y in terms of x

x= -16-t
y=19-4t

Answer 1

1)1-x>= 0 and x+1>=0 x>=-1 and x<=1 so for f+g and f-g the domain is -1<=x<=1
sqrt((1+sqrt(1-x)) 1+sqrt(1-x)>=0 always if 1-x>=0 so x<=1
f/g the same as f+g except x=1(excluded)
2) y= 6x+2 so (y-2)/6 =x
Interchange x and y so the inverse is y=(x-2)/6
y=13x^3-7
(y+7)/13= x^3 so x = cubic root ((y+7)13)) y=[(x+7)/13)]^1/3
You should be able to do the others.
y=mx+b m is the slope and b the intercept with Oy
t=-16-x and t=(19-y)/4
so-16-x=(19-y)4
-64-4x=76-4y so 4x-4y +140 = 0 y= x +35