Check sibling questions

Slide28.JPG

Slide29.JPG

This video is only available for Teachoo black users

This video is only available for Teachoo black users

Get live Maths 1-on-1 Classs - Class 6 to 12


Transcript

Ex 3.3, 1 Prove that sin2 π/6 + cos2 π/3 – tan2 π/4 = – 1/2 Solving L.H.S sin2 π/6 + cos2 π/3 − tan2 π/4 Putting π = 180° = sin2 (180° )/6 + cos2 (180° )/3 – tan2 (180° )/4 = sin2 30° + cos2 60° – tan2 45° Putting sin 30° = 1/2 , sin 60° = 1/2 , tan 45° = 1 Ex 3.3, 1 Prove that sin2 π/6 + cos2 π/3 – tan2 π/4 = – 1/2 Solving L.H.S sin2 π/6 + cos2 π/3 − tan2 π/4 Putting π = 180° = sin2 (180° )/6 + cos2 (180° )/3 – tan2 (180° )/4 = sin2 30° + cos2 60° – tan2 45° Putting sin 30° = 1/2 , sin 60° = 1/2 , tan 45° = 1 = (𝟏/𝟐)^𝟐 + (𝟏/𝟐)^𝟐 – 12 = 1/4+ 1/4 −1 = (1 + 1 − 4 )/4 = (−2)/4 = (−𝟏)/𝟐 = R.H.S. Hence proved

Ask a doubt
Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.