# Bilinear symmetrical term as the product of two means

**URL:** <https://community.freefem.org/t/bilinear-symmetrical-term-as-the-product-of-two-means/1403>\
**Category:** General Discussion\
**Created:** [December 23, 2021, 3:24pm UTC](https://community.freefem.org/t/bilinear-symmetrical-term-as-the-product-of-two-means/1403 "2021-12-23T15:24:44Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![munch](https://avatars.discourse-cdn.com/v4/letter/m/a4c791/32.png) [@munch](https://community.freefem.org/u/munch)\
**Post date:** [December 23, 2021, 3:24pm UTC](https://community.freefem.org/t/bilinear-symmetrical-term-as-the-product-of-two-means/1403/1 "2021-12-23T15:24:44Z")

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Hi all,

is there a way to consider bilinear term of the form

(\int\_\Omega \phi dx ) (\int\_\Omega \phi\_t dx)

\phi\_t being the test function ?

Thanks, arnaud

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**Author:** ![frederichecht](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/frederichecht/32/15_2.png) [@frederichecht](https://community.freefem.org/u/frederichecht)\
**Post date:** [December 24, 2021, 12:47pm UTC](https://community.freefem.org/t/bilinear-symmetrical-term-as-the-product-of-two-means/1403/2 "2021-12-24T12:47:37Z")

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OK, thés is a full matrix  
ann you can compute this matrix with a  
varf vf(psi, phi) = (\int\_\Omega \phi dx );  
real[int] V = vf(0,Vh) ; // with FreeFEM notation

then the matrix associated to your bilinear form is  
the outer product of V and V ie:  
A = V\*(V^t) ;