First cell

3!

5!

345

345+34567

a

a+a

Pi

N[Pi]

N[Pi,100]

1234567891023456789102345689012345678

1234567891023456789102345689012345678+1

1234567891023456789.102345689012345678+1.

123!

Pi^2

Pi^2.

N[Pi^2]

Sin[Pi]

Sin[N[Pi]]

Cos[1]

Cos[1.]

N[Cos[1]]

N[1]

Cos[N[1]]

[ ]

( )

(* comment *)

{ }

[[ ]]

?Plot

?*Plot

?Plot*

a^b/a

13/27(3/4)^(-1/2)

123!/2^123

E

I

D=4

D

Plot

Cos[Pi]

Cos@Pi

Pi//Cos

123!/2^123  //Cos //N

Factorial

Power

t = 4

Set[t,4]

aux = 56^56^2;

IntegerDigits[aux]//Length

Length[aux]

Sin[3]

Sin[a]

c=Sin[a,b]

c

sin[a]

sin[a,b]

x^2+x-3

x=3

{1,2,3,4,5}

{a,b,c,d}[[2]]

{{a,b,c,d}[[2]],c,a}

{{a,b,c,d}[[2]],c,a}[[2]]

{{a,b,c,d}[[2]],c,a}[[2]][[2]]

{a,b,c,d}//FullForm

Sin[a,b]//Length

Sin[a,b]//TreeForm

a+b+c+d//Length

a+b+c+d//FullForm

a+b+c+d//TreeForm

a+b+c+d

In[95]//TreeForm

a^b^c

%//FullForm

%%
%%%
%98

l = {1,2.3, I, Pi, f[4], f[g[h]]}

l={{2,3},4}

l={{1,2,3},{4,5,6},{10,-1,2}}

l//MatrixForm

l//ColumnForm

l//TableForm

?*Form

Sum[1/i^2,{i,1,10}]

Sum[1/i^2,{i,1,Infinity}]

Sum[1/i^2.5,{i,1,Infinity}]

Sum[1/i^(5/2),{i,1,Infinity}]

Zeta[(5/2)]//N

Sum[1/i^8,{i,1,Infinity}]

l

l//TreeForm

l

l[[1]]
l[[-1]]
l[[-2]]

l[[0]]

l[[1]][[2]]

l[[1,2]]

?Part

{a,b,3,4}[[0]]

Head[{a,b,3,4}]

f@{a,b,3,4}

Apply[f,{a,b,3,4}]

Apply[Plus,{a,b,3,4}]

Apply[Plus,f[a,b,3,4]]

Plus@@{1,2,3,4}

Plus@{1,2,3,4}

Clear[a,b,c,x]

x = Pi/E

?x

b = x E

c := x E

?SetDelayed

x = 3

b

c

?b

?c

f[x_]:=x^2

?f

f[4]

f[Pi]

f[3.5]

f[1,2.2]

f[x_,y_]:=x+y

?f

In[178]

f[Pi,Sin[E]+z]//Trace