Anyone familiar with Mathematica?

[MissJina]

I have 2 questions:

1. Solve sin x + cos x =Sqrt2, 0 lessthanequalto x lessthanequalto pi/2.

I can't figure out how to input this question into Mathematica...



2. Find the equation of the tangent to the curve y = x^2+1 at the point (2,4) and plot both the tangent and the graph on the same rectangular frame. Label the parabola curve as y=x^2 and the tangent line by its equation.

So for this I have so far...

input f[x_]:=x^2+1
input m[x_]:=D[f[x]]
input m[2]
then it gave me the output 5
input y-4=m[2](x-2)
output 5(-2+x)
input T=m[2](x-2)+4
output 4+5(-2+x)

and now I'm trying to plot it by...

input Plot[{T,x^2}{x,-5,5}]

but it won't plot for some reason and I get an error msg saying " Plot::argr: Plot called with 1 argument; 2 arguments are expected.

I have no clue what this means...is anyone here that knows how to use Mathematica!??!? Please helpppppp :D Thanks in advance!

 

[Char. Limit]

You don't need Mathematica for the first one if you remember that sin(pi/4) = cos(pi/4) = sqrt(2)/2.