| 1. |
5+2√3/7+4√3= a+b√3 Find the value of a and b |
|
Answer» Answer: mark me as brainiest Step-by-step EXPLANATION: GIVEN (5 + 2√3)/(7 + 4√3) = a + b√3 Rationalizing the denominator on left-hand-side by multiplying the numerator and denominator with (7 - 4√3), (5 + 2√3) (7 - 4√3)/(7 + 4√3) (7 - 4√3) = a + b√3 Multiply term by term the two expressions on numerator of L.H.S. and for the denominator APPLY the identity (m+n) (m-n) = m² - n² . We obtain, (35 - 20√3 + 14√3 - 8.√3.√3)/[7² - (4√3)²] = a + b√3 Or, (35 - 6√3 - 8.3)/(49 - 48) = a + b√3 Or, (35 - 6√3 - 24)/1 = a + b√3 Or, 11 - 6√3 = a + b√3 Now equate the rational and irrational terms from both sides. 11 = a Or, a = 11 - 6√3 = b√3 ⇒ b = -6 |
|