ข้อ2)ของคุณคนรักคณิต
$$\int_0^1 \int_{-1}^1[\int_0^{y^2} dz]dydx$$
$$=\int_0^1 \int_{-1}^1[y^2]dydx=\int_0^1 [\int_{-1}^1 y^2 dy]dx$$
$$=\int_0^1 [\frac{y^3}{3}]_{-1}^1] dx =\int_0^1 [\frac{2}{3}] dx$$
$$=\int_0^1 \frac{2}{3} dx=\frac{2}{3}\int_0^1 dx=\frac{2}{3}$$
ปล.ใช่ไหมครับ
