Question 25

Sin A + Sin$$^{2}\ $$A = 1, then the value of cos$$^{2}\ $$A + cos$$^{4}\ $$A is

Solution

Given sin A+$$sin^{2}$$ A=1

==> sin A = 1-$$sin^{2}$$ A

==> sin A = $$cos^{2}$$ A ($$\because cos^{2}A+sin^{2}A$$=1)

$$cos^{2}$$ A=sin A ==> $$cos^{4}A$$=$$sin^{2}A $$

$$\therefore cos^{2}A+cos^{4}A=1 ( \because sin A+sin^{2}A=1)$$

Share on Whatsapp Share on Whatsapp

Create a FREE account and get: