Question

lgctg 2° + lgctg 88º.

Answer 1

$\displaystyle\bf\\\lg Ctg 2^\circ+\lg Ctg88^\circ=\lg Ctg 2^\circ+\lg Ctg(90^\circ-2^\circ)=\\\\\\=\lg Ctg 2^\circ+\lg tg2^\circ=\lg (Ctg 2^\circ\cdot tg2^\circ)=\lg1=0$