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$574^2$ = $(572+2)^2$

ATQ,

$572^2$ = 327184

Therefore, by using $(a + b)^2 = a^2 + b^2 + 2ab$

$(572+2)^2$ = $572^2$ + $2^2$ + 2 x 572 x 2

                 = 327184 + 4 + 2288

                 = 329476

Thus,

$574^2$ = 329476

We can rewrite $574^2$ as $(572+2)^2$ . And we know that $(a+b)^2=a^2+b^2+2ab$

$(572+2)^2=\color{#D61F06}{572}^{\color{#D61F06}2}+2^2+2\times 2\times 572\\=\color{#D61F06}{327184}+4+2288\\=\boxed{329476}$