log2+16log(1615)+12log(2524)7log(8180)
=log2+16[log16−log15]+12[log25−log24]+7[log81−log80][l∵log(ab)=loga−logb]
=log2+16[log24−log(3×5)]+12[log52−log(8×3)][∵log(a)m=mloga]
=log2+64log2−16log3−16log5+24log5−36log2−12log3+28log3−7log5−28log2
=log2+log5