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Definition df-abs 15221
Description: Define the function for the absolute value (modulus) of a complex number. See abscli 15380 for its closure and absval 15223 or absval2i 15382 for its value. For example, (absโ€˜-2) = 2 (ex-abs 30283). (Contributed by NM, 27-Jul-1999.)
Assertion
Ref Expression
df-abs abs = (๐‘ฅ โˆˆ โ„‚ โ†ฆ (โˆšโ€˜(๐‘ฅ ยท (โˆ—โ€˜๐‘ฅ))))

Detailed syntax breakdown of Definition df-abs
StepHypRef Expression
1 cabs 15219 . 2 class abs
2 vx . . 3 setvar ๐‘ฅ
3 cc 11142 . . 3 class โ„‚
42cv 1532 . . . . 5 class ๐‘ฅ
5 ccj 15081 . . . . . 6 class โˆ—
64, 5cfv 6551 . . . . 5 class (โˆ—โ€˜๐‘ฅ)
7 cmul 11149 . . . . 5 class ยท
84, 6, 7co 7424 . . . 4 class (๐‘ฅ ยท (โˆ—โ€˜๐‘ฅ))
9 csqrt 15218 . . . 4 class โˆš
108, 9cfv 6551 . . 3 class (โˆšโ€˜(๐‘ฅ ยท (โˆ—โ€˜๐‘ฅ)))
112, 3, 10cmpt 5233 . 2 class (๐‘ฅ โˆˆ โ„‚ โ†ฆ (โˆšโ€˜(๐‘ฅ ยท (โˆ—โ€˜๐‘ฅ))))
121, 11wceq 1533 1 wff abs = (๐‘ฅ โˆˆ โ„‚ โ†ฆ (โˆšโ€˜(๐‘ฅ ยท (โˆ—โ€˜๐‘ฅ))))
Colors of variables: wff setvar class
This definition is referenced by:  absval  15223  absf  15322  absfico  44594
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