问题 解答题 2×2+4×4+6×6+…+50×501×1+2×2+3×3+…+25×25. 答案 2×2+4×4+6×6+…+50×501×1+2×2+3×3+…+25×25,=(1×1+2×2+3×3+…+25×25)×21×+2×2+3×3+…+25×25,=2.