The 8th term of 3x+23x212 when expanded in ascending power of x, is

When 3x+23x212 is expanded, the power of x goes on decreasing as the terms proceed. Hence, it is expanded in descending powers of x. So 23x2+3x12,when expanded, will be in ascending powers of x.Now,t8 in 23x2+3x12=12C723x212−7 =12!7!5!⋅23x25⋅(3x)7 =12×11×10×9×85×4×3×2⋅25⋅32x3 =228096x3