Question

20 x 4 x cos 45 degree​

Answer 1

Answer:

20×4×1/√2

40√2

this is your answer

Answer 2

$20(4)(cos45)\\20(4)(\frac{1}{\sqrt{2} })\\ 20(\sqrt{2} )^3\\20(2\sqrt{2} )\\40\sqrt{2}$