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If $f$ is continuous on the closed interval $[2,7]$ , then $\int_{2}^{7}f(x)\,dx=\int_{2}^{4}f(x)\,dx+\int_{4}^{7}f(x)\,dx$
If $g$ is continuous on the closed interval $[3,25]$ , then $\int_{3}^{10}g(x)\,dx=\int_{3}^{25}g (x)\,dx+ \int_{25}^{10}g(x) dx$