Question

find the value of sin^2 5° + sin^2 10° + sin^2 15° +.........+sin^2 90°​

Answer 1

Answer:

what's this question say and what

Answer 2

Answer:

Step-by-step explanation:

sin25∘+sin210∘+sin215∘+...+sin285∘+sin290∘

=sin2(90−85)∘+sin2(90−80)∘+sin2(90−75)∘+...sin275∘+sin280∘+sin285∘+sin290∘

=cos285∘+cos280∘+cos275∘+...+sin245∘+...+sin275∘+sin280∘+sin285∘+sin290∘

=(cos285∘+sin285∘)+(cos280∘+sin280∘)+...(cos240∘+sin240∘))+sin245∘+sin290∘

=1+1+1+1+1+1+1+1+12+1

=9.5

∴sin25∘+sin210∘+sin215∘+...+sin285∘+sin290∘=9.5