log 2=0,3010&amp;#10; log 3=0,4771&amp;#10; log 7=0,8451&amp;#10;\\a.log 18&amp;#10; log 3.3.2&amp;#10; =log 3+log3+log 2&amp;#10; =log3+log3+log2&amp;#10; =0,4771+0,4771+0,3010&amp;#10; =1,2552&amp;#10;\\b.log 21&amp;#10; log 7.3&amp;#10; =log7+log 3 =0,8451+0,4771&amp;#10; =1.3222&amp;#10;&amp;#10;\\c.log 10,5&amp;#10; =log 21/2&amp;#10; =log 7.3/log2&amp;#10; =log 7+log3-log2 =log 7+log3-log2&amp;#10; =0,8451+0,4771-0,3010&amp;#10; =1,0212&amp;#10;&amp;#10;\\d.log 1/7&amp;#10; =log 7/49&amp;#10; =log 7-log 7.7&amp;#10; =log 7-log7-log7&amp;#10; =-log 7&amp;#10; =-0,8451