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kropki game

The zero of a function is a number, which put to a formula of function give value equals zero. The zero of a function can be obtain from graph of a function. Examples. y = x + 2, x_0 = -2, because if put -2 in place x then obtain 0. y = 2x-6, x_0 = 3, because if put 3 in place x then obtain 0.