integral 0 to 1 [2x]

∫₀¹[2x] dx= [2x²/2] 0 to 1

           = [x²] 0 to 1

           = 1² - 0²

           = 1

sorry sir.but i didnt understand this step-([2x]=[2x^2/2]) by the way sir,there is no 1 in answer choices

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