Q15 of 116 Page 6

If find the value of .

Given that,

x + = 12


Squaring both sides, we get


(x + )2 = 122


x2 + ()2 + 2 × x × = 144


x2 + = 142


Subtract 2 from both sides, we get


x2 + - 2 × x × = 142 – 2


(x - )2 = 140


x - = �


More from this chapter

All 116 →
13

Find the values of the following expressions:

(i)


(ii)


(iii)

14

If find the value of

16

If 2x+3y=14 and 2x-3y=2, find value of xy. [Hint: Use (2x+3y)2 –(2x-3y)2 = 24xy]     

 17

if x2+y2 = 29 and xy = 2, find the value of

(i) x+y


(ii) x-y


(iii) x4+y4