document.write( "Question 1187141: Obtain the first 4 terms in the expansion of (1+2x)^9 in ascending powers of x.Use this expansion to find an approximate value of (1.02)^9. \n" ); document.write( "
Algebra.Com's Answer #819233 by Boreal(15235)\"\" \"About 
You can put this solution on YOUR website!
the first term is 9C0(1^9)(2x)^0=1
\n" ); document.write( "the second term is 9C1*(1^8)(2x)^1=18x
\n" ); document.write( "the third term is 9C2*(1^7)*(2x)^2=36*4x^2=144x^2
\n" ); document.write( "the fourth term is 9C3*(1^6)(2x)^3=84*8x^3=672x^3\r
\n" ); document.write( "\n" ); document.write( "here, x=0.01
\n" ); document.write( "so the sum is 1+0.18+0.0144+0.000672=1.195072
\n" ); document.write( "1.195092 is the actual answer to 6 decimal places
\n" ); document.write( "
\n" );