Question

Упростите 5√10(8-9√40)-13√90

Answer 1

$5 \sqrt{10} \times (8 - 9 \sqrt{40)} - 13 \sqrt{90} = 40 \sqrt{10} - 45 \sqrt{400} - 13 \sqrt{90} = 40 \sqrt{10} - 900 - 39 \sqrt{10} = 1 \sqrt{10} - 900$