CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

Use direct method to evaluate :

(i) (x + 1)(x - 1)

(ii) (2 + a)(2 - a)

(iii) (3b - 1)(3b + 1)

(iv) ( 4 + 5x)(4 - 5x)

(v) (2a + 3)(2a - 3)

(vi) (xy + 4)(xy - 4)

(vii) (ab + x^2)(ab - x^2)

(viii) (3x^2 + 5y^2)(3x^2 - 5y^2)

(vi) (xy + 4)(xy - 4)

(ix) (z23)(z+23)

(x) (35a+12)(35a12)

(xi) (0.5 - 2a)(0.5 + 2a)

(xii) (a2b2)(a2+b3)


Solution

(i) (x+1)(x1)=(x)2(1)2

=x21

(ii) (2+a)(2a)=(2)2(a)2

=4a2.

(iii) (3b - 1)(3b + 1) = (3b)2(1)2

=9b21.

(iv) (4+5x)(45x)=(4)2(5x)2

=1625x2.

(v) (2a+3)(2a3)=(2a)2(3)2

=4a29.

(vi) (xy+4)(xy4)=(xy)2(4)2

=x2y216.

(vii) (ab+x2)(abx2)=(ab)2(x2)2

=9x425y4.

(ix) (z23)(z+23)=(z)2(23)2
=z249.

(x) (35a+12)(35a12)

=(35a)2(12)2=925a214.

(xi) (0.5 - 2a)(0.5 + 2a)

=(0.5)2(2a)2

=0.254a2.

(xii) (a2b3)(a2+b3)=(a2)2(b3)2

=a24b29.


Mathematics
Concise Mathematics
Standard VIII

Suggest Corrections
thumbs-up
 
1


similar_icon
Similar questions
View More


similar_icon
Same exercise questions
View More


similar_icon
People also searched for
View More



footer-image