The value of sin² 65° + sin² 25° + cos²

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The value of sin² 65° + sin² 25° + cos² 35° + cos² 55° is

1. 0
2. 1
3. 2
4. 1
  2

Correct Option: C

Expression = sin² 65° + sin² 25° + cos²35° + cos² 55°
= sin² 65° + sin² (90° – 65°) + cos² 35° + cos² (90° – 35°)
= sin² 65° + cos² 65° + cos² 35° + sin² 35°
= 1 + 1 = 2