formatting - HoldForm does not Hold Form for fractions sometimes

I'm facing a strange behavior of HoldForm.

I need to display 1/2*3/4 in LaTeX like this : $$ \frac{1}{2} \times \frac{3}{4} $$

So I use Mathematica : 1/2* 3/4 // HoldForm // TeXForm BUT I get $$ \frac{3}{2\ 4} $$

First the writing 2 space 4 is ambigous and second it does not hold form at all :(

Can you help me ? Thank you ! (happy Holidays)

EDIT : I would need an automatic transformation of any input to correct TeX or an automatic correction of any output to correct TeX.

Answer

Use HoldForm applied to each fraction to keep the fractions from combining.

HoldForm[1/2] HoldForm[3/4]

to produce $$ \frac{1}{2} \frac{3}{4} $$

HoldForm[(1/2) (3/4)]

to produce $$ \frac{3}{2 \times 4} $$

Using TeXForm produces the desired LaTex code.

(HoldForm[1/2] HoldForm[3/4]) // TeXForm
(* \frac{1}{2} \frac{3}{4} *)

Addendum

Simpler is

Infix[f[1/2, 3/4], "\[Times]"] // TeXForm
(* \frac{1}{2}\times \frac{3}{4} *)

which also provides the times sign. $$\frac{1}{2}\times \frac{3}{4}$$

Second Addendum

z1 z2 /. Times -> Cross /. {z1 -> 1/2, z2 -> 3/4} // TeXForm

also produces the desired output. (This is based on the third Answer to 39061.)

Comments

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