Cho biết \(\int\limits_0^3 {f\left( z \right)dz} = 3,\int\limits_0^4 {f\left( x \right)} dx = 7.\). Hãy tính \(\int \limits_3^4 f\left( t \right)dt.\)
Ta có:
\(\begin{array}{l}
\int\limits_3^4 f \left( t \right)dt = \int\limits_3^0 f \left( t \right)dt + \int\limits_0^4 f \left( t \right)dt\\
= - \int\limits_0^3 f \left( t \right)dt + \int\limits_0^4 f \left( t \right)dt\\
= - 3 + 7 = 4
\end{array}\)
-- Mod Toán 12