Perpendicular lines are lines, segments or rays that intersect to form right angles. The symbol ⊥ means is perpendicular to .
It A⊥ means orthogonal complement of A, meaning the subspace that consists of all vectors which when dotted with any vector from A produce 0, that is. A⊥={→x | →x⋅→y=0, ∀→y∈A}
The upside down capital T means
The up tack or falsum (⊥, \bot in LaTeX, U+22A5 in Unicode) is a constant symbol used to represent: The truth value 'false', or a logical constant denoting a proposition in logic that is always false (often called "falsum" or "absurdum").
what does the upside down T mean. In geometry, it means "is perpendicular to".
Check for Ice Crystals A small layer of ice crystals on ice cream or other foods is normal, and probably won't affect the flavor. Large ice crystals or a thick layer of ice are a sign that the food will not taste fresh.
A D battery (D cell or IEC R20) is a standardized size of a dry cell. A D cell is cylindrical with an electrical contact at each end, the positive end has a nub or bump. A D cell may be either rechargeable or non-rechargeable. Its terminal voltage and capacity depend upon its cell chemistry.