If 3x+13x=3, then find 9x2+19x2.
Given, 3x+13x=3Squaring both sides, (3x+13x)2=9Applying the formula (a+b)2=a2+b2+2ab3x2+(13x)2+2×3x×13x=99x2+19x2+2=9=>9x2+19x2=7