展开 cos(2t)-cos(2t)U(t-pi)

解答

展开

cos (2 t) - cos (2 t) U (t - π)

cos (2 t) - t U cos (2 t) + π U cos (2 t)

求解步骤

cos (2 t) - cos (2 t) U (t - π)

= cos (2 t) - U cos (2 t) (t - π)

乘开

- cos (2 t) U (t - π) : - t U cos (2 t) + π U cos (2 t)

= cos (2 t) - t U cos (2 t) + π U cos (2 t)

e x p an d (x - 1) d x

e x p an d \frac{125 ( 2 n + 3 ) ^{2} ( 2 n + 4 ) ^{2}}{4}

e x p an d (2 π - 45)^{2}

e x p an d U (t - 4) (2 - t^{2}) + 2 e^{- π t} + sin (3 t) - t^{3}

e x p an d \frac{( x ^{4} - 1 ) ^{2}}{4 x ^{4}}