Submitted on: 02 November 2022.
Revised on: 22 February 2023.
Accepted on: 07 April 2023.
___________________Bulletin of the Karaganda University-Mathematics
Submitted on: 26 December 2020.
Revised on: 25 January 2021.
Accepted on: 09 March 2021.
___________________Bulletin of the Karaganda University-Mathematics
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Submitted on: 30 September 2013.
Revised on: 30 December 2013.
Accepted on: 08 February 2014.
___________________Bulletin of the Karaganda University-Mathematics
Submitted on: 17 February 1999.
Revised on: 11 March 1999.
Accepted on: 05 May 1999.
___________________Bulletin of the Karaganda University-Mathematics
http://reply.papertrans.cn/1/44/4376/4376-16.png
Submitted on: 06 September 2019.
Revised on: 05 November 2019.
Accepted on: 20 December 2019.
___________________Bulletin of the Karaganda University-Mathematics
Submitted on: 10 March 2023.
Revised on: 01 June 2023.
Accepted on: 24 June 2023.
___________________Bulletin of the Karaganda University-Mathematics
Submitted on: 09 November 2015.
Revised on: 03 December 2015.
Accepted on: 25 December 2015.
___________________Bulletin of the Karaganda University-Mathematics
Submitted on: 31 May 2014.
Revised on: 18 September 2014.
Accepted on: 06 November 2014.
___________________Bulletin of the Karaganda University-Mathematics