document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1096826>Question 1096826</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 3a. The first three terms of an arithmetic sequence are u1 = 0.3, u2 = 1.5, u3 = 2.7. <BR>\n" );
document.write( "Find the common difference. <BR>\n" );
document.write( "3b. Find the 30th term of the sequence. <BR>\n" );
document.write( "3c. Find the sum of the first 30 terms.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #711336 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52793)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=711336\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "The first three terms of an arithmetic sequence are u1 = 0.3, u2 = 1.5, u3 = 2.7. \r<BR>\n" );
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document.write( "3a.  Find the common difference.                   It is  u2-u1 = 1.5 - 0.3 = 1.2.\r\n" );
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document.write( "3b.  Find the 30th term of the sequence.           It is  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=u%5B30%5D ALIGN=MIDDLE  ALT=\"u%5B30%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=u%5B1%5D%2B29%2A1.2 ALIGN=MIDDLE  ALT=\"u%5B1%5D%2B29%2A1.2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 0.3 + 29*1.2.   Calculate it on your own.\r\n" );
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document.write( "3c.  Find the sum of the first 30 terms.           It is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28u%5B1%5D%2Bu%5B30%5D%29%2F2%29%2A30 ALIGN=MIDDLE  ALT=\"%28%28u%5B1%5D%2Bu%5B30%5D%29%2F2%29%2A30\"   DISABLED_style= \"max-width:90%; height:auto;\" >.    As  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=u%5B30%5D ALIGN=MIDDLE  ALT=\"u%5B30%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > use the value that you find at n. 3b.\r\n" );
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document.write( "On arithmetic progressions, see introductory lessons  in this site:\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/Sequences-and-series/Arithmetic-progressions.lesson>Arithmetic progressions</A>\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/Sequences-and-series/The-proofs-of-the-formulas-for-arithmetic-progressions.lesson>The proofs of the formulas for arithmetic progressions</A> \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/Sequences-and-series/Problems-on-arithmetic-progressions.lesson>Problems on arithmetic progressions</A>  \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/Sequences-and-series/Word-problems-on-arithmetic-progressions.lesson>Word problems on arithmetic progressions</A>\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/Sequences-and-series/Solved-problems-on-arithmetic-progressions.lesson>Solved problems on arithmetic progressions</A> \r<BR>\n" );
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document.write( "Also, &nbsp;you have this free of charge online textbook in ALGEBRA-II in this site\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-II - YOUR ONLINE TEXTBOOK</A>.\r<BR>\n" );
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document.write( "The referred lessons are the part of this online textbook under the topic <U>\"Arithmetic progressions\"</U>.\r<BR>\n" );
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document.write( "Save the link to this textbook together with its description\r<BR>\n" );
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document.write( "Free of charge online textbook in ALGEBRA-II<BR>\n" );
document.write( "https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson\r<BR>\n" );
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document.write( "into your archive and use when it is needed.\r<BR>\n" );
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