knotty vs problematical

knotty and problematical both are adjectives.

Word	Noun	Adjective	Verb	Adverb
knotty	No	Yes	No	No
problematical	No	Yes	No	No

As adjectives, knotty and problematical are synonyms defined as:

knotty and problematical: making great mental demands; hard to comprehend or solve or believe

Other synonyms of knotty include baffling, elusive, problematic, tough.

knotty (adjective)	problematical (adjective)
highly complex or intricate and occasionally devious	making great mental demands; hard to comprehend or solve or believe
used of old persons or old trees; covered with knobs or knots	open to doubt or debate
making great mental demands; hard to comprehend or solve or believe
tangled in knots or snarls