"asertain" is probably misspelled. Trying ascertain instead Definition of ascertain
1
[ verb ] after a calculation, investigation, experiment, survey, or study

Examples

"find the product of two numbers" "The physicist who found the elusive particle won the Nobel Prize"

2
[ verb ] be careful or certain to do something; make certain of something

Examples

"He verified that the valves were closed" "See that the curtains are closed" "control the quality of the product"

3
[ verb ] find out, learn, or determine with certainty, usually by making an inquiry or other effort

Examples

"I want to see whether she speaks French" "See whether it works" "find out if he speaks Russian" "Check whether the train leaves on time"

4
[ verb ] give evidence

Examples

"he was telling on all his former colleague"

5
[ verb ] learn or discover with certainty
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