Question

sec² 10° – cot² 80° = ?

Options

• 0

• 1

• `3/4`

• `1/2`

Answer 1

1

Explanation:

Given expression = sec² 10° – cot²(90° – 10°)

= sec² 10° – tan² 10°   ...[∵ sec²θ – tan²θ = 1]

= 1