Question

i tan 48° tan 23° tan 42° tan 67° =1 .​

Answer 1

Answer:

0

Step-by-step explanation:

Show that : (i) tan 48° tan 23° tan 42° tan 67° = 1 (ii)

cos 38° cos 52° – sin 38° sin 52° =0

Answer 2

Step-by-step explanation:

By solving LHS

tan(90°-42°) tan(90°-67°)tan42° tan67°

{Since tan(90°-A)=cotA}

cot42°cot67°tan42°tan67°

{since cotA=1/tanA}

1/tan42° ×tan42° ×1/tan67° ×tan67°

1

hence proved