Question 131

If sin 21°= x/y then sec21°- sin 69° is equal to

Solution

Given , sin 21°= x/y . So , cos21°=$$\sqrt{1-sin^{2}21°}$$ . cos21=$$\sqrt{1-(\frac{x}{y})^{2}}$$
So, sec21°= $$\frac{1}{cos21^{\circ}}$$
Also sin69°=cos21°.
Hence, sec21°-sin69° = $$\frac{1}{\sqrt{1-(\frac{x}{y})^{2}}}$$ - $$\sqrt{1-(\frac{x}{y})^{2}}$$
= $$\frac{x^2}{y\sqrt {y^2-x^2}}$$


Create a FREE account and get:

  • Free SSC Study Material - 18000 Questions
  • 230+ SSC previous papers with solutions PDF
  • 100+ SSC Online Tests for Free

cracku

Boost your Prep!

Download App