Question

Suppose an isosceles triangle ABC has A = PI/4 and b = c = 4. What is the length of a^2?
a) 4^(2)(2-SQR2))
b) 4^(2)(SQR2)
c) 4^(2)(2+SQR2)
d) 4^(2)(SQR2 -2)

Answer 1

a

Answer 2

a² = b² + c² -2bc cos A
= 4² + 4² - 2(4)(4)* cos 45
= 16+16-32 (1/√2)
= 16+16-16(√2)
= 4² {2- √2 }

Answer 3

Thanks :)